A is the brother of B, C is the mother of A, D is the father of C, and F is the son of A. In this multigeneration blood relation question, how is A related to the child of F?

Introduction / Context:
This question links four people across several generations: A, B, C, D and F. We know how A is related to B, who C is to A, who D is to C and that F is the son of A. We then need to identify the relation of A to the child of F. The problem mainly tests recognition of grandparents in a family tree.

Given Data / Assumptions:
• A is the brother of B, which means A is male.• C is the mother of A, so C is one generation above A.• D is the father of C, so D is two generations above A.• F is the son of A, so F is one generation below A.• We are asked for the relation between A and the child of F.

Concept / Approach:
F is given clearly as the son of A. The child of F is therefore one more generation below F. From the perspective of A, F is a child and the child of F is a grandchild. Because A is male, he will be a grandfather to this grandchild. So, A is the grandfather of the child of F. The chain across generations is what matters here, not the intermediate relatives D and C, which mainly confirm the generational order.

Step-by-Step Solution:
Step 1: From A is brother of B, confirm that A is male.Step 2: C is mother of A, placing C one generation above A.Step 3: D is father of C, placing D two generations above A.Step 4: F is son of A, placing F one generation below A.Step 5: The child of F is one more generation down from F.Step 6: Any person whose child has a child is a grandparent to that second child.Step 7: Since A is male, he is the grandfather of the child of F.

Verification / Alternative check:
If we draw the generations, D sits at the top, then comes C, then A and B, then F, and finally the child of F. This gives five levels. A is on the third level and the child of F is on the fifth. There are exactly two generational steps between A and the child of F, confirming a grandparent and grandchild relationship. Because the intermediate step from A to F is parent and child, the step from A to the child of F must be grandparent and grandchild.

Why Other Options Are Wrong:
Aunt of the child: An aunt is a sister of a parent; A is male and also the direct parent of the father, not a sibling.Cousin of the child: Cousins share grandparents; A is one of those grandparents here, not a cousin.Nephew of the child: This reverses generations and would make A younger than the child, which is impossible with the given data.Brother of the child: A brother shares the same parents as the child, not a child's grandparent.

Common Pitfalls:
Often, candidates ignore the simple generational structure and overthink the role of D and C, although they are not needed to answer the question about the child of F. Remember that once you know F is the son of A, it is enough to see that A is parent of F and grandparent of F's child. Keeping track of generations consistently avoids confusion.

Final Answer:
A is the grandfather of the child of F.