A, B, C, D, E, F and G are members of a family consisting of four adults and three children, two of whom, F and G are girls. A and D are brothers and A is a doctor. E is an engineer married to one of the brothers and has two children. B is married to D and G is their child. Who is C ?

Explanation:-

E is married to A or D. But, S is married to D. Thus, E is married to A. Thus, A, B, D, E are the four adults and C, F, G are the three children in the family. B and D have a child G. A and E have two children---C and F. Now, only F and G are girls. So, C is a boy. Thus, C is A's or E's son.