Consider the following relationships among members of a family of six persons A, B, C, D, E and F:
- 1.The number of males equals that of females.
- 2.A and E are sons of F.
- 3.D is the mother of two, one boy and one girl.
- 4.B is the son of A.
- 5.There is only one married couple in the family at present.
Which one of the following inferences can be drawn from the above?
Answer & explanation
Answer: (b) A is the husband of D.
A, E and B are sons, so they are the three males, and C, D and F are the three females. D's son must be B, because A and E are F's sons; so D is B's mother and A is B's father. With only one married couple, A is D's husband.
- A and E are sons of F, and B is the son of A — so A, B and E are males. Equal numbers means C, D and F are the three females.
- D is the mother of a boy and a girl. Her boy cannot be A or E, whose mother is F, so it is B.
- B's father is A and B's mother is D, so A and D are the only married couple.
- D's girl is C; F, the mother of A, belongs to the older generation.
- So A is the husband of D.
- ✗ (a) A and B are sons, so they are males.
- ✓ (b) A is B's father and D is B's mother; with only one married couple, A and D are husband and wife.
- ✗ (c) E is F's son, and F is A's mother, so neither is D's child.
- ✗ (d) F is the mother of A, D's husband, so F is D's mother-in-law, not her mother.
Remember · In family puzzles, fix genders first from 'son', 'mother' and similar words, then use 'only one married couple' to pair the parents.
Question and answer: UPSC's official GS Paper II (2017, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·