In a family of 6 members(A, B, C, D, E & F), D is the only son of A, E is the grandfather of D. B is the daughter-in-law of C. F is the uncle of D. C is wife of A. What is the relationship of B with D?

Wife

In the above diagram,

= represents husband and wife relation.

+ represents male and - represents female.

Upper arrow represents upper generation and low arrow represents lower generation.

So, according to the given data, B is the wife of D.