P is the brother of Q and R. S is R's mother. T is P's father.
Which of the following statements cannot be definitely true ?

E. Q IS T'S SON.

A family consists of six members P, Q, R, S, T and U. There are two married couples. Q is a doctor and the father of T. U is grandfather of R and is a contractor. S is grandmother of T and is a housewife. There is one doctor, one contractor, one nurse, one housewife and two students in the family. Who is the husband of P ?

C. Q

(I).   A, B, C, D, E and F are six members of a family.
(II).  One couple has parents and their children in the family.
(III). A is the son of C and E is the daughter of A.
(IV). D is the daughter of F who is the mother of E. What relationship do D and E bear to each other ?

D. SISTER

A man and his wife have three sons, and every of the sons has a sister. How many are there in the family ?

C. 6

A, B, C, D, E, F and G are members of a family consisting of four adults and three children, two of whom, F and G are girls. A and D are brothers and A is a doctor. E is an engineer married to one of the brothers and has two children. B is married to D and G is their child.
Who is C ?

A. A'S SON