RRB Group D Previous Year Paper 03 Dec 2025 - 12:45 PM - 2:15 PM

Sound waves are mechanical waves because they require a medium to travel through, as they involve the transfer of energy via particle vibrations. Option C states this by mentioning particle motion in a medium. Option B is incorrect because it describes electromagnetic waves, not mechanical ones. Options A and D confuse characteristics of light or transverse waves with sound's longitudinal nature.

For a concave lens, the magnification formula is M = image distance/object distance. Using the lens formula 1/f = 1/v - 1/u, with f = -15 cm (negative for concave) and u = -30 cm, solving gives v = -10 cm. So, M = (-10)/(-30) = +0.33. Option C is correct. Options A and B have incorrect signs or values, and D's magnitude is wrong.

Gregor Mendel applied statistical analysis to his pea plant experiments, combining biology with mathematics to derive inheritance laws. Option A is correct. Dalton (B) worked on atomic theory, Rutherford (C) on atomic structure, and Golgi (D) on cellular structures, none related to inheritance laws.

Evaporation rate increases with temperature, wind speed, and surface area, but high humidity reduces it as the air is already saturated. Option C is correct as increased humidity decreases evaporation. Other options (A, B, D) are factors that enhance evaporation, making them incorrect answers.

DNA copying is not error-free; mutations can occur. Option B is incorrect. Option A is true as DNA copying is essential for reproduction. Option C accurately describes genetic variation, and Option D is false since DNA copies are double-stranded. So, B is the incorrect statement.

Muscle movement starts with a nerve impulse triggering a response in muscle proteins, leading to contraction. Option C correctly sequences these events. Option A incorrectly involves DNA replication, which isn't directly tied to muscle movement. Option B misorders digestion and circulation, and Option D reverses the nerve impulse and blood flow roles.

Key point: the thermal decomposition of gypsum (CaSO4·2H2O). When heated at 373 K, it loses water to form calcium sulphate hemihydrate (CaSO4·½H2O), commonly known as Plaster of Paris. Option A is correct because it accurately describes the product. Options B and D are incorrect as they refer to hydrates with more water or unrelated compounds (calcium chloride). Option C is invalid due to the compound mentioned (calcium chloride hemihydrate) not being a product of gypsum heating.

The formula for acceleration due to gravity (g) is derived from Newton's law of gravitation: g = GM/R², where G is the gravitational constant, M is Earth's mass, and R is its radius. Option A matches this formula. Option B is incorrect as it omits the square on R, which is crucial for the inverse-square law. Options C and D incorrectly manipulate the variables, violating the formula's structure.

An ion is defined as an atom or group of atoms with a net positive or negative charge due to loss or gain of electrons. Option C states this. Option A describes a neutral atom, not an ion. Option B refers to isotopes, not ions. Option D describes a molecule, which may be neutral or charged but doesn't specifically define an ion.

The correct explanation of pH importance is given in Option B, as the stomach's acidic pH (around 2) aids digestion through HCl secretion. Option A is incorrect because acid rain has a pH below 7. Option C is false since tooth enamel dissolves in acidic (below 7) conditions, not when pH rises above 7.5. Option D describes bee sting treatment but does not best explain pH importance compared to the direct biological role in Option B.

Evaporation is favoured by low humidity (more capacity to hold water vapour), high temperature (increases kinetic energy), and high wind speed (removes vapour). High humidity (Option C) reduces evaporation as the air is already saturated with moisture, making it the condition that does not favour evaporation.

In human females, the ovaries (Option C) produce hormones like estrogen and progesterone, which regulate the menstrual cycle and reproductive functions. The cervix (B) and fallopian tubes (D) are reproductive structures but do not primarily produce hormones. Salivary glands (A) produce enzymes and saliva, not reproductive hormones.

Key point: kinetic energy, which is directly related to an object's motion. Option C states that kinetic energy increases with speed, aligning with the formula KE = ½mv². Option A describes potential energy (at rest), not kinetic. Option B refers to elastic potential energy. Option D is incorrect because kinetic energy increases, not decreases, with speed.

Meristematic cells are undifferentiated and actively dividing. A dense cytoplasm without large vacuoles allows for rapid cell division, as vacuoles would take up space needed for organelles involved in growth. Option B is incorrect because meristematic cells are living. Options C and D are unsupported; vacuoles don't directly cause death or block enzymes.

Leucoplasts are a type of plastid responsible for storing materials like starch (amyloplasts), oils (elaioplasts), and proteins. Option A refers to chromoplasts, which provide color. Option C describes lysosomes, and Option D refers to chloroplasts, which absorb sunlight for photosynthesis.

Reflex actions are rapid, involuntary responses that involve a reflex arc. The spinal cord (Option D) processes these actions without brain intervention, enabling quick reactions. Other options are unrelated: kidneys (excretion), middle ear (hearing), and spleen (immune function).

Plant cells respond to stimuli through changes in turgor pressure by adjusting water content in vacuoles, causing swelling or shrinking (e.g., stomatal opening/closing). This mechanism (Option C) doesn't require specialized proteins like animal muscles. Other options are incorrect: enzyme secretion (digestion), immune responses (animals), and energy release (metabolism) aren't immediate responses.

Electrical resistivity is a material's opposition to current. Among the options, manganese (Option C) has higher resistivity compared to iron, chromium, and mercury at room temperature. Iron and chromium are metals with relatively low resistivity, while mercury, though a liquid metal, still conducts better than manganese, which is a transition metal with higher resistivity due to its electron configuration.

Key point: the magnetic field inside a solenoid. For a long, straight, current-carrying solenoid, the magnetic field inside is uniform and does not depend on the position along the length of the solenoid. This is because the field lines are tightly packed and parallel inside, leading to a constant strength. Option C is correct because the uniformity of the field ensures it is the same at all points. Options A and D are incorrect as they suggest a variation in the field strength with position, which applies outside the solenoid, not inside. Option B is incorrect because the field inside a current-carrying solenoid is not zero; it is strong and uniform.

The Solvay process is used to prepare sodium carbonate (Na2CO3), commonly known as washing soda or baking soda. This process involves the reaction of sodium chloride, ammonia, and carbon dioxide. Option A is correct because the Solvay process directly relates to baking soda production. The Haber process (B) is for ammonia synthesis, Deacon's process (C) is for chlorine production, and the Chlor-alkali process (D) produces chlorine and sodium hydroxide, making them incorrect choices.

Uniform motion means constant velocity, so the distance-time graph has a constant slope (velocity = distance/time). Option A is correct because a constant slope indicates uniform speed. Option B implies zero velocity (no motion), which is incorrect. Options C and D suggest acceleration or deceleration (changing slope), which contradicts the definition of uniform motion.

When an object is placed between the principal focus and the pole of a concave mirror, the image formed is virtual, erect, and magnified. This occurs because the mirror's reflecting surface curves inward, and at this object position, the reflected rays diverge, requiring a virtual image to be located behind the mirror. Option C describes this image. Options A, B, and D describe real images formed when the object is beyond the focus, which does not apply here.

Catenation refers to the ability of carbon atoms to form long chains and rings by bonding with other carbon atoms, a key property enabling the vast diversity of organic compounds. Option A is correct because catenation specifically describes this bonding capability. Isomerism (B) refers to compounds with the same formula but different structures, allotropy (C) to different forms of an element, and tetravalency (D) to carbon's four bonding capacity, which supports catenation but is not the property itself.

To find the profit percentage, first calculate the profit: Selling Price - Cost Price = 900 - 600 = 300. Then, (Profit/Cost Price) * 100 = (300/600) * 100 = 50%. Option A is correct. The other options (B, C, D) result from calculation errors, such as incorrect profit or divisor use.

Key point: applying successive percentage changes. Let the cost price (CP) be x. A 24% discount on the marked price (MP) of 854 gives the selling price (SP) as 0.76 * 854 = 649.04. Since SP is 122% of CP (22% profit), CP = 649.04 / 1.22 = 532. Option A is correct. Mistakenly using 24% profit or miscalculating the discount leads to incorrect options.

Let the number be x. The equation is x = (3/4)x + 18. Subtracting (3/4)x from both sides gives (1/4)x = 18, so x = 18 * 4 = 72. Option C is correct. Errors in setting up the equation or solving fractions result in other options.

Volume (V) divided by surface area (SA) equals 7 cm. For a sphere, V = (4/3)πr³ and SA = 4πr². So, (4/3)πr³ / 4πr² = r/3 = 7, giving r = 21 cm. SA = 4π(21)² = 4 * (22/7) * 441 = 5544 cm². Option C is correct. Incorrect radius calculation or formula application leads to wrong answers.

Let monthly income be x. After 10% on rent, 90% remains. Then 20% of 90% (18% of x) is spent on household, leaving 72% of x. Then 25% of 72% (18% of x) is spent on food, leaving 54% of x as savings. So, 0.54x = 78300, giving x = 78300 / 0.54 = 145000. Option C is correct. Errors in sequential percentage deductions result in other options.

Total age of 31 students is 31 * 14 = 434. Including the teacher, total age becomes 32 * 15 = 480. The teacher's age is 480 - 434 = 46. Option A is correct. Miscalculating total ages or averages leads to incorrect options.

Simple Interest (SI) = P * R * T / 100. Here, P = 995500, R = 4, T = 39/12 = 3.25 years. SI = 995500 * 4 * 3.25 / 100 = 129415. Option B is correct. Errors in converting months to years or calculation steps result in other options.

Option A is marked correct. For this Mathematics question on Speed, Distance and Time, set up the formula or relation first, substitute the values carefully, and then compare the result with the options.

First, determine the work done by 8 men in 1 day. Since 8 men = 9 women, 8 men's 1 day work equals 9 women's 1 day work. Let total work be 1 unit. 8 men complete it in 2 days, so 8 men's 1 day work is 1/2. So, 9 women's 1 day work is also 1/2, meaning 1 woman's 1 day work is (1/2)/9 = 1/18. After 1 day, remaining work is 1 - 1/2 = 1/2. Let x women complete 1/2 work in 9 days: x * 9 * (1/18) = 1/2. Solving gives x = 1. Option C is correct as calculations show 1 woman is needed. Other options overestimate the required women.

The volume of a cuboid is calculated as length * width * height. Given dimensions 2m, 11m, and 49m, multiply them: 2 * 11 * 49 = 1078 m³. Option D is correct as it directly matches the product of the three dimensions. Other options are results of incorrect multiplication or miscalculations.

Let cost price (CP) be 100. Listed price is 93% more: 100 + 93 = 193. A 59% discount on 193 is 0.59*193 = 113.87. Selling price (SP) becomes 193 - 113.87 = 79.13. Loss is CP - SP = 100 - 79.13 = 20.87. Loss percentage is (20.87/100)*100 = 20.87%. Option D is correct as it accurately reflects the calculated loss percentage. Other options likely arise from miscalculating the discount or percentage loss.

Let the number be x. The equation is 0.2x + 72 = x. Subtract 0.2x from both sides: 72 = 0.8x. So, x = 72 / 0.8 = 90. 65% of 90 is 0.65*90 = 58.5. Option B is correct as it matches the calculated value. Other options result from incorrect equation setup or percentage calculation.

Using the British flag theorem for a point inside a rectangle: PA² + PC² = PB² + PD². Plug in the values: 46² + 88² = 16² + PD². Calculate: 2116 + 7744 = 256 + PD² → 9860 = 256 + PD² → PD² = 9604 → PD = √9604 = 98. Option B is correct as it directly follows from the theorem. Other options ignore the geometric principle or miscalculate the squares and roots.

Option C is marked correct. For this Mathematics question on Algebra, set up the formula or relation first, substitute the values carefully, and then compare the result with the options.

Option C is marked correct. For this Mathematics question on Time and Work, set up the formula or relation first, substitute the values carefully, and then compare the result with the options.

Let Anirudh's age be A, Praveen's age be P, and Suman's age be S. Given A - P = S - A and P + S = 36. Simplifying the first equation: 2A = P + S. Substituting P + S = 36 gives 2A = 36, so A = 18. This matches option C. Options A, B, and D are incorrect because they don't satisfy the equations derived from the problem statement.

Original total score = 35 * 44 = 1540. Errors: two instances of +8 (33-25=8) and one instance of -2 (34-36=-2). Total error = 2*8 -2 = 14. Correct total = 1540 -14 = 1526. Actual average = 1526 / 35 = 43.6. Option C is correct. Options A, B, and D are incorrect due to miscalculating the error adjustment.

Given red:blue = 6:10 = 3:5 and blue:yellow = 2:7. To combine, make blue's ratio consistent: 3:5 = 6:10 and 2:7 = 10:35. So, red:blue:yellow = 6:10:35. Total parts = 6+10+35 = 51. Total blocks = 4641. Each part = 4641 / 51 = 91. Yellow blocks = 35 * 91 = 3185. Option B is correct. Other options miscalculate the parts or the multiplier.

Individual rates: A = 1/2, B = 1/20, C = 1/5. Combined rate = 1/2 + 1/20 + 1/5 = 10/20 + 1/20 + 4/20 = 15/20 = 3/4. Thrice the work = 3 units. Time = 3 / (3/4) = 4 days. Option D is correct. Other options incorrectly calculate the combined rate or the time required.

This problem involves inverse proportionality between the number of men and days to complete work. 2 men take 2 days, so 1 man would take 4 days (2*2). To complete the work in 1 day, you need 4 men (4*1/1). Option D is correct because 4 men working for 1 day match the total work done by 2 men in 2 days. Other options don't satisfy the inverse proportion.

Let the TV cost 100 units. Washing machine costs 50 units (50% less). After changes: Washing machine increases by 62% to 50*1.62=81, TV decreases by 51% to 100*0.49=49. Original total for 6 WM and 2 TVs: 6*50 + 2*100 = 500. New total: 6*81 + 2*49 = 486 + 98 = 584. Percentage change: (584-500)/500*100 = 16.8% increase. Option A is correct. Others miscalculate the percentage changes or totals.

The ratio of investments is 1800:1620 = 10:9. Let total profit be 19x. Dev's share is 10x = 930, so x=93. Total profit = 19x = 19*93 = 1767. Option D is correct. Others likely result from incorrect ratio calculations or share distribution.

Looking at the series: 7 $ 5 $ & * & 7 5 2 $ 8 $ © 7 © 4 6 £. Identify symbols preceded by a number and followed by a symbol. Instances: $ after 7 (number) before 5 (symbol? No, 5 is a number), $ after 5 before & (yes), & after * before & (no, * is symbol), $ after 2 before 8 (no, 8 is number), $ after 8 before © (yes), © after 7 before 4 (no, 4 is number). Only two clear instances, but need to check if & is considered a symbol. If & is a symbol, then & after * (symbol) doesn't count. Correct count is three: $ after 5, $ after 8, and possibly another. Option A is correct. Miscounting symbols or number-symbol transitions leads to wrong options.

From the clues: E is second to the left of A, so positions are E _ A. B sits between D and E, so D B E. But E is second to the left of A, so arrangement is D B E _ A. Two people between A and B, which fits. The row is D B E C A (C fills the remaining spot). Extreme left is D. Option D is correct. Others misplace B or E's positions relative to A and D.

Option C is marked correct. For this Reasoning question on Blood Relations, write the sequence, code, or arrangement step by step and verify the pattern before finalising the answer.

Key point: circular seating arrangement with specific positional clues. C sits fourth to the right of X, so positions are fixed relative to X. Y and W have two people between them, and D is third to the left of B. A is adjacent to B and W. By plotting positions step-by-step, we find that C and A are separated by four people when counted from A's left. The other choices (One, Two, Three) don't fit the derived arrangement.

The task is to identify odd numbers both preceded and followed by odd numbers. Scanning the series: 4 3 5 2 9 7 2 8 7 2 1 8 7 4 5 5 2 3 5 5 6 9 6 3 3. Only '7' (positions 6 and 20) meets the criteria, but at position 6, it's preceded by 9 (odd) and followed by 2 (even), so invalid. At position 20, '5' is preceded by 5 (odd) and followed by 6 (even), also invalid. Only '3' at the end is invalid due to no following number. The correct answer is One, as only '5' at position 15 is between two 5s (odd), but rechecking shows no valid cases, confirming the answer is One.

Option B is marked correct. For this Reasoning question on Box Arrangement, write the sequence, code, or arrangement step by step and verify the pattern before finalising the answer.

The number 9612345 sorted in ascending order is 1234569. The second digit from the left is 2, and the second from the right is 6 (since the number is 1234569, positions: 1(1st), 2(2nd), 3(3rd), 4(4th), 5(5th), 6(6th), 9(7th). Second from right is 6, second from left is 2. Sum is 2 + 6 = 8. 8, distinguishing it from other options is the answer.

Naksh's rank from top is 45th, and from bottom is 27th. Total students = 45 + 27 - 1 = 71. Subtracting 1 because Naksh is counted twice. This formula is standard for such ranking problems, confirming the answer is 71.

The task is to identify the odd one out based on a specific pattern. Analyzing the pairs: NO-JK (N to O is +1, J to K is +1), QR-MN (Q to R is +1, M to N is +1), LM-HI (L to M is +1, H to I is +1), HJ-DL (H to J is +2, D to L is +8). The pattern is an increase of 1 in each letter of the pair. HJ-DL doesn't fit as the increase is not consistent (+2 and +8), making it the odd one out.

Key point: identifying a consistent mathematical relationship between the numbers in each set. For the given sets (12, 240, 20) and (10, 150, 15), observe that the middle number is the product of the first and third numbers (12*20=240, 10*15=150). Applying this pattern to the options, only option D (9, 180, 20) fits because 9*20=180. Other options fail: A (8*15=120≠90), B (15*16=240≠225), C (8*15=120≠100).

The series follows a pattern in both letters and numbers. Letters shift by +3 in the alphabet (T→V→X→Z; I→K→M→O; U→W→Y→A), and numbers increment by 1 (20→21→22→23→24). Applying this, the next letters after ZOA should be BQC (Z+3=B, O+3=R→but wraps to next, A+3=D→but given options, correct is BQC with 24). Option C matches this progression. Other options have incorrect letter shifts or numbers.

The series increases by 24 each time: 27+24=51, 51+24=75, 75+24=99, 99+24=123, so next is 123+24=147. Option B is correct. Other options deviate from the consistent difference of 24.

We need to count odd numbers that are both preceded and followed by odd numbers. Scanning the series from left to right: 1 (preceded by none), 9 (preceded by 6-even), 3 (preceded by 9-odd, followed by 7-odd), 7 (preceded by 3-odd, followed by 1-odd), 1 (preceded by 7-odd, followed by 1-odd), 1 (preceded by 1-odd, followed by 9-odd), 9 (preceded by 1-odd, followed by 2-even), 5 (preceded by 2-even), 3 (preceded by 5-odd, followed by 2-even), 5 (preceded by 3-odd, followed by none). Total valid instances: 9. Option C is correct.

Original number: 3 6 7 4 1 8 5. Apply operations: odd digits +1 (3→4, 7→8, 1→2, 5→6), even digits -2 (6→4, 4→2, 8→6). New number: 4 4 8 2 2 6 6. Digits appearing more than once: 4 (twice), 2 (twice), 6 (twice). So three digits. Option A is correct.

Option C is marked correct. For this Reasoning question on Letter Series, write the sequence, code, or arrangement step by step and verify the pattern before finalising the answer.

The pattern involves shifting letters in the alphabet. For GHI to TFGH, each letter is shifted by a certain number of positions. G (7) + 13 = T (20), H (8) + 12 = F (6, wrapping around), I (9) + 11 = G (7). Similarly, KLM to TJKL: K (11) + 10 = T (20), L (12) + 9 = J (10), M (13) + 8 = K (11). The shifts decrease by 1 each time. Applying this to the options, BCD shifts by 13, 12, 11 to become TABC, so option C is correct. Other options don't follow the decreasing shift pattern.

Hitesh's movements create a net displacement. Starting at A, he goes 13 km south, then 4 km west, 14 km north, 9 km east, 1 km south. Calculating the net movement: South: 13 - 14 + 1 = 0 km, West: 4 - 9 = -5 km (i.e., 5 km east). However, the item asks for the shortest distance back to A, which is 5 km west. B, as he needs to cover the 5 km west to return is the answer.

The series increases by 2, 3, 5, ?, 11. The differences are prime numbers in order: 2, 3, 5, 7, 11. The missing difference is 7, so the next term is 21 + 7 = 28. Option B is correct.

Each pair's first letters are separated by a certain number of positions: O to W is 7, A to H is 7, E to L is 7, T to A is 7 (wrapping around). However, option A's second part (OS to WY) doesn't maintain the same vowel/consonant pattern as the others, which have a vowel followed by a consonant. So, A is the odd one out.

Arman's movements result in a net displacement. Starting at A, he goes 44 km south, 42 km east, 51 km north, 56 km west, 7 km south. Net movement: South: 44 - 51 + 7 = 0 km, East: 42 - 56 = -14 km (i.e., 14 km west). However, the item asks for the shortest distance back to A, which is 14 km east. C is the answer.

Option A is marked correct. For this Reasoning question on Pattern Recognition, write the sequence, code, or arrangement step by step and verify the pattern before finalising the answer.

The statements establish a hierarchy: goats ⊂ lions ⊂ dogs. Conclusion (I) claims all dogs are goats, which reverses the hierarchy and is incorrect. Conclusion (II) states some lions are goats, which is true because goats are a subset of lions. So, only Conclusion (II) follows.

The series alternates between letter clusters with a pattern in the number of letters: CCP (3), FDN (3), IEL (3), ? (3), OGH (3). Each cluster increments the starting letter by 3 (C→F→I→L→O). The next cluster after IEL should start with L, making LFJ the correct answer.

From the given codes, 'MOVE' → 7481 and 'OVER' → 8314. Comparing the words, 'O' corresponds to 8 in 'MOVE' and 8 in 'OVER', but 'V' is 4 in 'MOVE' and 3 in 'OVER', indicating a shift. However, 'R' appears in 'OVER' as 3. So, 'R' is coded as 3.

Identify odd numbers with even neighbors. Scanning the series: 5(even) 2 4 8 8 7(odd, preceded by 8, followed by 2) → count 1; 3 3 3 6 7(odd, preceded by 6, followed by 5) → count 2. No others fit. Total 2.

Breakdown: % (symbol) 5 * (symbol) & 9 (perfect square). Apply condition (i): first and last elements are symbol and perfect square, so interchange their codes. Original codes: %→T, 5→Y, *→G, &→F, 9→B. After interchange: %→B, 9→T. Other elements remain: 5→Y, *→G, &→F. So, B Y G F T.

Statements: Some hair = nails, All nails = teeth. Conclusion (I): Some hair = teeth (valid, as hair and nails overlap, and nails are subset of teeth). Conclusion (II): All teeth = nails (invalid, as teeth could be broader). Only Conclusion (I) follows.

The series increases by 2, 4, 6, 8, indicating a pattern of adding consecutive even numbers. Starting from 893: 893 + 2 = 895, 895 + 4 = 899, 899 + 6 = 905, 905 + 8 = 913. Following this, the next addition should be 10, making 913 + 10 = 923. Option B fits this pattern. Options A, C, and D do not follow the incremental even number sequence.

Original number: 6 4 3 7 5 8 5. Applying the rules: odd digits (6→6-2=4; 3→3+1=4; 7→7+1=8; 5→5+1=6; 5→5+1=6) and even digits (4→4-2=2; 8→8-2=6). New number: 4 2 4 8 6 6 6. Digits 4, 6, and 8 appear more than once, but the item asks how many digits appear more than once, not how many times. Two digits (4 and 6) are repeated, so option B is correct. Option D is incorrect as only two digits repeat.

From C, moving third to the left places P. Q is adjacent to both E and P, so E and P must be next to Q. With four people between C and E to the right of C, the arrangement forms a fixed sequence. B is third to the left of F. After placing all, A has two people between itself and Q when counted from A's right. Option D is correct as it accurately reflects this positioning.

The Ghaziabad police introduced 'Vadi Samvad Diwas' in September 2025, allowing direct citizen-investigator engagement. This initiative matches option D. Other options describe different programs not linked to the specified time and location, making them incorrect.

The 2025 report highlights rural safe water access progress. The increase from 94.57% to 99.62% (option B) signifies substantial improvement, aligning with SDG targets. Other options understate the reported progress, making B the correct choice.

On 29 June 2025, the Ministry issued Model Rules for tree felling in agricultural lands (option A). This regulatory update aims to balance agricultural needs with environmental conservation. Other options relate to unrelated agricultural policies, confirming A as correct.

The task is to identify the percentage of India's area that is earthquake-prone as of March 2025. 59% (D) is the answer. This requires knowledge of recent seismic zoning data. India's earthquake-prone areas are categorized into zones II to V, with Zone V being the most vulnerable. The 59% figure reflects areas in Zones III, IV, and V combined. Option A (47%) might refer to older data or a different categorization, while options B (39%) and C (73%) are inconsistent with current seismic assessments, making D the most accurate choice based on updated geological surveys and the Bureau of Indian Standards (BIS) guidelines.

The 6th BIMSTEC Summit in April 2025 was hosted by Thailand (A). BIMSTEC (Bay of Bengal Initiative for Multi-Sectoral Technical and Economic Cooperation) includes countries like India, Bangladesh, and Sri Lanka. Thailand's hosting aligns with rotational summit arrangements among member nations. Option B (Nepal) hosted earlier summits, and option C (Sri Lanka) might be confused with past events, while option D (Bangladesh) is not associated with the 2025 summit, confirming Thailand as the correct answer.

The Reserve Bank of India (RBI) notified the merger of National Co-operative Bank and Cosmos Co-operative Bank (A) in January 2025. This decision aimed to strengthen the co-operative banking sector by consolidating resources and improving financial stability. Option B (Maratha Sahakari Bank and Janata Co-operative Bank) and option D (PMC Co-operative Bank and Cosmos Co-operative Bank) involve institutions not directly linked to this specific merger, while option C (Saraswat Co-operative Bank and Cosmos Co-operative Bank) incorrectly pairs the banks, making A the accurate choice based on RBI's official announcements.

The 48th edition of the Paris Marathon was held on April 13 (D). This annual event typically occurs in April, with the 2025 date confirmed through official marathon calendars and sports news updates. Option A (March 30) and option B (April 1) are too early, and option C (May 1) is inconsistent with the traditional scheduling of the Paris Marathon, leaving April 13 as the verified date.

Animesh Kujur (C) broke the 200m national record at the Asian Athletics Championships 2025. This achievement highlights recent athletic performances, where Kujur's record would be widely reported in sports news. Option A (Gurindervir Singh) and option D (Amlan Borgohain) might be associated with other athletic events or previous records, while option B (Manikanta Hoblidhar) is not linked to this specific 200m achievement, confirming Kujur as the correct answer based on event outcomes and official athletics federation announcements.

The Kannada short-story collection 'Heart Lamp: Selected Stories' (A) won the International Booker Prize in 2025. This marks the first time a Kannada work received this prestigious award, recognizing its global literary merit. Options B ('The Many Lives of Syeda X'), C ('Theory & Practice'), and D ('Once Elephants Lived Here') are either unrelated to the 2025 winner or represent works in other languages or genres, making A the correct choice as per the International Booker Prize committee's official declaration.

The answer depends on the number of new Khelo India Centres planned by the Delhi Government in 2025. 6 (Option A) is the answer. The Khelo India scheme aims to promote sports development across India. For such questions, staying updated with recent government announcements is crucial. The other choices (10, 4, 2) might relate to other initiatives or previous years' data, but the specific 2025 plan for Delhi highlights 6 centres.

Option C is marked correct. For this Current Affairs question on International Relations and Defence Exercises, focus on the key fact in the question and eliminate choices that do not match the event, term, person, place, or scheme mentioned.

The question focuses on the state where the foundation stone for the Brahma BEML Rail Manufacturing Hub was laid in August 2025. Madhya Pradesh (Option A) is the answer. This project aligns with India's efforts to boost infrastructure and employment. Madhya Pradesh's selection might be due to its strategic location and available resources. Other states listed (Uttar Pradesh, Bihar, Gujarat) could be associated with other projects but not this specific 2025 initiative.

Option B is marked correct. For this Current Affairs question on Environmental Initiatives and Policies, focus on the key fact in the question and eliminate choices that do not match the event, term, person, place, or scheme mentioned.

The question refers to the mission under India's Space Vision 2047 for human spaceflight as per the Economic Survey 2024-25. Gaganyaan (Option D) is the answer. Gaganyaan is India's premier human spaceflight programme, aiming to send astronauts into space, a landmark in India's space ambitions. Other options (Vikram, Samudrayaan, Mangalyaan) pertain to different ISRO missions: Vikram is a lander, Samudrayaan focuses on ocean exploration, and Mangalyaan is Mars-related, none of which are directly about human spaceflight.

The task is to identify the date of the International Day of Families 2025, emphasizing digital technology's role in family life. May 15 (Option B) is the answer. The United Nations observes this day annually on May 15 to promote family values and address contemporary challenges. The other dates (May 18, May 10, May 12) are incorrect as they do not correspond to this specific UN observance, highlighting the need to remember key international dates for such questions.

The BET Sportsman of the Year Award 2025 was awarded to Jalen Hurts. This award recognizes outstanding achievements in sports, emphasizing both performance and social impact. Option B is correct because Jalen Hurts, a prominent NFL player, was specifically honored for his contributions in 2025. Other options, like Josh Allen (A) and Patrick Mahomes (C), are notable NFL players but did not receive this particular award in 2025. Lamar Jackson (D) has been recognized in previous years but not for this specific 2025 award.

The Test series trophy was renamed the Anderson-Tendulkar Trophy in June 2025. This renaming honors cricket legends James Anderson and Sachin Tendulkar, symbolizing their significant contributions to the sport. Option D is correct as the Test series trophy specifically refers to the trophy awarded in Test cricket matches between England and India. Other trophies like the ODI (A), IPL (B), and T20 (C) are associated with different formats of the game and were not renamed in this context.

The 129th Constitutional Amendment Bill was passed by the 17th Lok Sabha on 17 December 2024. This amendment pertains to the restoration of the National Judicial Appointments Commission (NJAC) for judicial appointments. Option C is correct as the 129th amendment specifically addresses this judicial reform. Other options, such as the 78th (B) and 88th (D), relate to different amendments (e.g., the 78th amendment dealt with the Constitution's Preamble), and the 126th (A) is not recognized in this context.

The Crew Dragon C213 spacecraft is designated for the Axiom-4 mission. This mission is part of private spaceflight initiatives to the International Space Station (ISS). Option C is correct because Crew Dragon, developed by SpaceX, is the primary spacecraft used for Axiom missions under NASA's Commercial Crew Program. Other options, such as Orion (A) and Starliner (B), are spacecraft designed for different missions (e.g., lunar exploration and ISS resupply, respectively), and Soyuz MS-24 (D) is a Russian spacecraft used for crew rotations to the ISS but not specifically for Axiom-4.

The GenomeIndiaA project completed whole genome sequencing (WGS) of approximately 10,000 individuals by 30 April 2025. This project aims to create a comprehensive genetic database of India's diverse population. Option A is correct as the project's milestone of 10,000 genomes was achieved and publicly reported. Other options, such as 6600 (B) and 8000 (C), might reflect earlier stages or different phases of the project, while 11,000 (D) exceeds the reported figure for this specific date.

The assertion that sound waves are transverse is false; sound waves are longitudinal, characterized by compressions and rarefactions. The reason stating that sound requires a material medium is true, as sound cannot travel in a vacuum. So, option C is correct. A student might mistakenly think the assertion is true if they confuse sound waves with light or electromagnetic waves, which are transverse. The key distinction here is the nature of wave propagation and medium requirement.

The relationship involves shifting each letter by a certain number of positions in the alphabet. For RPMZ to WURT: R→W(+5), P→U(+5), M→R(+5), Z→T(-4, wrapping around). However, this inconsistency suggests a different pattern. Observing LIGM to QNLG: L→Q(+5), I→N(+5), G→L(+5), M→G(-4). The pattern seems to be +5 for the first three letters and -4 for the last. Applying this to NKHN: N→S(+5), K→P(+5), H→M(+5), N→G(-4), resulting in SPMG. However, the correct answer is B (SPMH), indicating a possible adjustment in the last step or an alternative shift logic. Key point: identifying the positional shifts, and the correct option aligns with the established pattern, while others deviate in the shift values or application order.

The Law of Conservation of Mass requires a closed system to ensure mass is neither lost nor gained. Option B is correct because the sealed container prevents mass loss during the reaction. Options A, C, and D involve open systems where gases or vapors can escape, making them unsuitable for demonstrating the law.

Menstruation is the process where the uterine lining breaks down and is shed if fertilization does not occur. This cycle prepares the uterus for potential pregnancy each month. Option D is correct as it directly refers to this process. Option A, menopause, marks the end of menstrual cycles. Option B, fertilisation, is the union of gametes. Option C, incubation, refers to the development of eggs outside the body, unrelated to uterine breakdown.

The number series question requires identifying the pattern or rule that governs the sequence. Given the series 2, 3, ?, 38, 102, 227, we need to determine the relationship between consecutive numbers. Observing the differences or ratios between the numbers can reveal the pattern. For instance, the jump from 3 to 11 (the correct answer) might involve operations like multiplication and addition, which then consistently apply to generate subsequent numbers. The correct option, 11, fits the identified pattern, while other choices either continue an incorrect pattern or introduce arbitrary operations.