In Relation puzzle type, mutual blood relations or other information of more than two persons are mentioned and information about any two is mentioned.
A is the father of C. But C is not his son.
E is the daughter of C. F is the spouse of A.
B is the brother of C. D is the son of B.
G is the spouse of B. H is the father of G.
Who is the grandmother of D ?
D is the son of B, B is the brother of C and A is the father of C. This means that B is the father of D and A is the father of B. So, A is the grandfather of D. Now, F is the spouse of A. So, F is the grandmother of D.