In Relation puzzle type, mutual blood relations or other information of more than two persons are mentioned and information about any two is mentioned.
There are six children playing football namely A, B, C, D, E and F.
A and E are brothers. F is the sister of E. C is the only son of A's uncle.
B and D are the daughters of the brother of C's father.
How is D related to A ?
Clearly, D's father is the brother of C's father and C's father is A's uncle.
So, D's father is also A's uncle.
Thus, D is A's Cousin.
Hence, the answer is (d).