Step-by-step Solution:

Quick Solution

This puzzle requires combining clues about family relationships and weight to determine the two married couples. We'll solve it by first establishing the weight ranking of the family members.

1. Deduce the Weight Ranking

• Clue 6 says E is heavier than B (E > B).
• Clue 2 says B is heavier than D and F (B > D and B > F).
• Clue 4 says C is heavier than E (C > E).
• Combining these gives a partial order: C > E > B > (D and F).
• Clue 7 says the grandfather is the heaviest, and clue 3 says C is not the heaviest. The only person not yet in our ranking is A. Therefore, A must be the grandfather and is the heaviest person.
• The full weight ranking is: A > C > E > B > D/F.

2. Identify Couple #1 (The Grandparents)

• The key is clue 5: "E who married a person heavier than C."
• From our weight ranking, the only person heavier than C is A.
• Therefore, E is married to A. This is the first couple.
• Since A is the grandfather (male), E must be the grandmother (female).

3. Identify Couple #2

• The remaining family members are B, C, D, and F.
• We know their genders from the clues: B is male, C is female, and D is male (as he is a brother).
• Clue 1 states that D and F are siblings, so they cannot be a married couple.
• The only remaining pair that can form the second married couple is B (male) and C (female).

Final Answer: The two married couples are (A, E) and (B, C). From the options given, BC is a married couple.