|A) 1||B) 2|
|C) 3||D) 4|
D is father of A and grandfather of F. So, A is father of F.
Thus, D and A are the two fathers. C is the sister of F So, C is the daughter of A.
Since there is only one mother, it is evident that E is the wife of A and hence the mother of C and F.
So, B is brother of A There are three brothers. So, F is the brother of C.
A, the father. is male B, the brother, is male, C, the sister, is female D, the grand-father, is male, E, the mother, is female F, the brother, is male.
So, there are four males.