Question

Looking at a portrait of a man, Akhil said, 'His mother is the wife of my father's son. Brothers and sisters I have none.' At whose portrait was Akhil looking ?
A) His uncle
B) His nephew
C) His cousin
D) His son

Answer 1

He was looking at a portrait of his son

Answer 2

D) His son  

Since Akhil  has no brother or sister, so he is his father's only son.  

Now, wife of my father's son -- my wife.  

So, Akhil's wife is the man's mother or the man is Akhil's son.