Which of the following is/are a couple/couples ?
- (a) AD only
- (b) BC only
- (c) Both AD and BC ✓ UPSC's answer
- (d) Both AC and BD
Why the answer is (c)
• D is the grandmother of F, and F is the son of B, so B is D's child and D is B's parent.
• C is the lawyer and the daughter-in-law of D, meaning C is married to B (since B is D's child and C is the daughter-in-law).
• The judge is married to the lawyer (C), so B must be the judge.
• A is the engineer and is married to the lady stenographer; since B is the judge and C is the lawyer, A cannot be married to B or C.
• The remaining members are E (unmarried doctor) and F (draughtsman). A must be married to the lady stenographer, who must be one of the females. Since C is the lawyer and D is the grandmother, the lady stenographer is not C or D. E is the doctor. Thus, the lady stenographer must be the wife of A. Wait, let's re-evaluate the couples.
• Couples are defined by marriage. We established B (Judge) is married to C (Lawyer). This is one couple: BC.
• A (Engineer) is married to the lady stenographer. Who is the lady stenographer? The professions are Engineer (A), Stenographer (?), Doctor (E), Draughtsman (F), Lawyer (C), Judge (B). The remaining profession is Stenographer. The remaining person is D? No, D is grandmother. The people are A, B, C, D, E, F. Professions: A=Eng, B=Judge, C=Lawyer, E=Doctor, F=Draughtsman. The only person left without a profession assigned in the direct list is D. So D is the Stenographer.
• A is married to the lady stenographer (D). So A is married to D. This is the second couple: AD.
• Therefore, the couples are AD and BC.
Why the other options are wrong
- (a) AD only
- Option (a) is incorrect because it excludes the couple BC, where B (Judge) is married to C (Lawyer).
- (b) BC only
- Option (b) is incorrect because it excludes the couple AD, where A (Engineer) is married to D (Stenographer).
- (d) Both AC and BD
- Option (d) is incorrect because A is married to D, not C, and B is married to C, not D.
Asked in the CSAT Paper II of the UPSC Civil Services Preliminary Examination 2014, held on 24 August 2014. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.