P has a son and a daughter. S is the mother of T. S is R's spouse. Q and R are children of P. Then how is Q related to S? (a) Q is a sister of S (b) Q is a daughter of S (c) Q is the mother of S (d) Q is a sister of the husband of S

UPSC Prelims 2026 · CSAT Paper 2 · Set DLogical ReasoningQ 24 / 80

UPSC Prelims 2026 CSAT Paper 2 — Question 24

Question

P has a son and a daughter. S is the mother of T. S is R's spouse. Q and R are children of P. Then how is Q related to S?

(a)Q is a sister of S
(b)Q is a daughter of S
(c)Q is the mother of S
(d)Q is a sister of the husband of S

UnlockIAS answer: (d)Q is a sister of the husband of S

Solution

S (a mother) is R's spouse, so R is male — P's son. Q is P's other child (the daughter), hence Q is R's sister, i.e. a sister of the husband of S.

UnlockIAS expert key, prepared 24 May 2026 and cross-verified by re-deriving the answer — this is our key, not the official UPSC provisional key (awaited).

Section

Logical Reasoning

Topic Reference

Logical Reasoning — Blood relations

Official UPSC key still awaited

UPSC has announced (PIB Release 2262441, 18 May 2026) that the provisional answer key for CSE Prelims 2026 will be released “soon after Exam”. Until then, use the CSAT score calculator for your qualifying-status estimate, and join the per-question discussion below.

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Official Notification

PIB Release 2262441

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