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QUESTION

CSAT

Hard

Reasoning

Prelims 2026

There are four statements XX, YY, ZZ and WW. Their relations are as follows: If XX is incorrect, then so is ZZ; if YY is incorrect, then WW is correct; if WW is correct, then XX is incorrect. Which of the following is/are correct? I. If XX is correct, then so is YY. II. If ZZ is correct, then it is not necessary that YY is correct. Select the answer using the code given below.

Select an option to attempt

Explanation

Let us represent the statements being correct as XX, YY, ZZ, and WW, and the statements being incorrect as $

eg X,,

eg Y,,

eg Z,and, and

eg W$.

According to the question, the given relations can be written as logical implications:

  1. If XX is incorrect, then ZZ is incorrect: $

eg X \implies

eg Z2.If2. IfYisincorrect,thenis incorrect, thenWiscorrect:is correct:

eg Y \implies W3.If3. IfWiscorrect,thenis correct, thenXisincorrect:is incorrect:W \implies

eg X$

By combining these three relations, we can form a continuous chain of implications: $

eg Y \implies W \implies

eg X \implies

eg Z$

In logic, the contrapositive of a statement A    BA \implies B is $

eg B \implies

eg A,andbothalwaysholdtheexactsametruthvalue.Takingthecontrapositiveofourentirechainofimplications(reversingtheorderandnegatingeachterm),weget:, and both always hold the exact same truth value. Taking the contrapositive of our entire chain of implications (reversing the order and negating each term), we get: Z \implies X \implies

eg W \implies Y$

Now, let us evaluate the given conclusions based on this contrapositive chain:

Statement I: If XX is correct, then so is YY. From our contrapositive chain, we can clearly see that X    YX \implies Y. This means that if XX is correct, YY must definitely be correct. Therefore, Statement I is correct.

Statement II: If ZZ is correct, then it is not necessary that YY is correct. From our contrapositive chain, we can see that Z    YZ \implies Y. This means that if ZZ is correct, it is absolutely necessary that YY is correct. Therefore, Statement II is incorrect.

Since only Statement I is correct, the correct option is A.

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