UPSC Prelims 2021 · CSAT (Paper II): What is the most logical assumption that can be made from the passage given…

UPSC Prelims 2021 · CSAT (Paper II)
Read the passage

With respect to what are called denominations of religion, if everyone is left to be a judge of his own religion, there is no such thing as religion that is wrong; but if they are to be a judge of each other’s religion, there is no such thing as a religion that is right, and therefore all the world is right or all the world is wrong in the matter of religion.

What is the most logical assumption that can be made from the passage given above ?

Answer (c) & explanation

The most logical assumption is that religious denominations tend to ignore the unity of man (c). Step 1: the passage says if each judges his own religion, all are right. But if each judges the others', none is right. Each group sees only its own view, so they divide people instead of seeing what they share. That is (c). Step 2: option (a) says no one can live without a religion; the passage does not say this. Option (b), a duty to spread one's religion, is also not stated. Step 3: option (d) says men do not understand their own religion; the passage never doubts that.

Tip: an assumption must sit underneath the author's argument. Reject options that bring in duties or needs the passage never mentions.

Answer as per the official UPSC answer key.

Same theme in UPSC Mains

Related questions from other years

UPSC Prelims 2026 · CSAT (Paper II)

Question : X receives three coins of different denominations : 1, 2, 5, 10 and 20. If the total amount received by X is m, does X receive a coin of denomination 5?

Statement I : m is not a prime number.

Statement II : The sum of the digits of m is greater than 5.

Answer (a) & explanation

Statement II alone is enough; Statement I alone is not (a). Step 1: three different coins from 1, 2, 5, 10, 20 give ten totals. With a 5: 8, 16, 17, 26, 27, 35. Without a 5: 13, 23, 31, 32. Step 2: Statement I (m not prime): 8, 16, 26, 27, 35 have a 5, but 32 (2 + 10 + 20) does not. Mixed answers, so I fails. Step 3: Statement II (digit sum above 5): 8, 16, 17, 26, 27, 35 qualify, and every one has a 5. (13, 23, 31, 32 have digit sums 4, 5, 4, 5.) So II answers "yes". Options (b), (c) and (d) fail.

Tip: when cases are few, list them all. Then check each statement against the full list.

Trap

don't assume both statements are needed. Listing all ten cases takes thirty seconds and settles it.

Answer as per the official UPSC answer key.

Open this question's page →

UPSC Prelims 2026 · CSAT (Paper II)
Read the passage

How is deflation done? Most countries use a method called ‘double deflation’, where input and output prices are deflated separately. Consider a manufacturer importing oil for use in production. If oil prices fall, output prices do not and quantities remain the same, real value added should not change. But if the same deflator is used for inputs and outputs, as in India, it would look as if the manufacturer had become more productive.

Which of the following assumptions is/are valid?

  • 1. Deflation strategies can be used to make manufacturers appear to be doing better than they actually are.
  • 2. When input and output prices are both deflated against a single input price, it is referred to as ‘double deflation’.

Select the answer using the code given below.

Answer (a) & explanation

Only assumption 1 is valid (a). Step 1: the passage says that using one deflator for inputs and outputs, as in India, makes it "look as if the manufacturer had become more productive". So deflation methods can make firms appear better than they are (1). Step 2: assumption 2 says double deflation means deflating both against a single price. But the passage defines double deflation as deflating inputs and outputs separately. So 2 reverses the definition. Step 3: options (b), (c) and (d) fail.

Tip: check definitions word for word against the passage. Deflating means removing the effect of price changes to find real growth, as in real GDP.

Answer as per the official UPSC answer key.

Open this question's page →

UPSC Prelims 2026 · CSAT (Paper II)

P, Q, R, S and T are ranked 1 to 5 (not necessarily in that order). The rank of P is 4, the rank of Q is not 5, the rank of R is 1, the rank of S is not 2, the rank of T is not 3. Then which of the following is/are correct?

  • I. If the rank of S is 3, then that of T is 2.
  • II. If the rank of Q is 3, then that of T is 5.

Select the answer using the code given below.

Answer (d) & explanation

Neither statement is correct (d). Step 1: P = 4 and R = 1 are fixed. Ranks 2, 3 and 5 remain for Q, S and T, with rules: Q is not 5, S is not 2, T is not 3. Step 2: statement I: if S = 3, then Q and T share 2 and 5. Q cannot be 5, so Q = 2 and T = 5, not 2. I is wrong. Step 3: statement II: if Q = 3, then S and T share 2 and 5. S cannot be 2, so S = 5 and T = 2, not 5. II is wrong. Options (a), (b) and (c) fail.

Tip: fix the known ranks first, then apply each "if" condition and let the "not" rules decide the rest. Write the small table on paper.

Answer as per the official UPSC answer key.

Open this question's page →

UPSC Prelims 2026 · CSAT (Paper II)

How many times does 5 appear in all two-digit positive integers?

Answer (b) & explanation

The digit 5 appears 19 times (b). Step 1: 5 in the tens place: 50, 51, …, 59 = 10 times. Step 2: 5 in the units place: 15, 25, 35, 45, 55, 65, 75, 85, 95 = 9 times (05 is not a two-digit number). Step 3: total = 10 + 9 = 19. The number 55 has two 5s, and both are counted. Option (a), 18, counts 55 once. Options (c) and (d) wrongly add 05 or 5.

Tip: count place by place. The question asks how many times the digit appears, not how many numbers contain it (that would be 18).

Answer as per the official UPSC answer key.

Open this question's page →