Explanation:

Correct option 3: P

Circle represents -Female

Square represents-Male

Double line represents -Couple.

single line represents - Sibling

Vertical line represnts - Generation

Dotted Line - Probable relation

From the given information,
1) P is the mother of T, P and Y are married couple (P is the wife of Y).
2) S is the mother of P and Y is the son in law of V (V is the husband of S).
3)S has only 2 children and R is the daughter in law of V (P has one brother and he is married to R).
4) R is the mother of Q and Q is the sister of W.
5) W is the granddaughter of S (we can identify the gender of W.
6) Both S and X has only two children (Thus, X is husband of R).
7) There are equal number of males and females (5 males and 5 females. Therefore, T and Z should be male, as of now we have 5 females).
8) There are two sisters (Q and W).
(There are two brothers, in order to satisfy this condition, we have to place Z in either with V or Y. We can't place Z with T because P has only one son.)
9) There are two brothers and two sisters (Hence, Z may be V or Y's brother).

All are males except P. Thus, P is the odd one.