We are given that:
- B is the brother of E's husband, so B is E's brother-in-law.
- D is the father of A and grandfather of F, which means D is A's father and F's grandfather.
- C is the sister of F, so C and F are siblings.
- There are 2 fathers, 3 brothers, and 1 mother, and F's father is mentioned.
Step 1: Understanding the Relationships.
From the clues, we can deduce:
- Since D is A’s father and the grandfather of F, A must be the father of F.
- F’s father is A, so A is one of the fathers.
- B is E’s brother-in-law, meaning B is married to E's sister (not A because A is F’s father).
- C and F are siblings, and C is the sister of F.
Step 2: Analyzing the Family Members.
- D is A's father and the grandfather of F, so A must be the father of F.
- B is married to E, and E is the mother of F, meaning B is F's uncle (brother of E’s husband).
- Since there are 3 brothers, B must be one of the brothers.
Final Answer:
\[
\boxed{A}
\]