A and B are brothers. C and D are sisters. A's son is D's brother.
How is B related to  C ?

A. Father
B. Brother
C. Grandfather
D. Uncle
E. None of these
Answer: D . Uncle


Clearly, B is the brother of A; A's son is D's brother. This means D is the daughter of A.
Since C and D are sister, C is also the daughter of A.
So, B is the uncle of C.
Hence, the answer is (d).