C is the daughter-in-law of A who is the grandmother of F means C is the mother of F But F is the son of B. 

So. B is C's husband. But C, the lawyer. is married to the Doctor So. B is the Doctor. F. the Accountant, will he the non of B and C E is the unmarried Engineer 

So. the other married couple can be that of grandmother of F. i.e, A and D. But D, the Salesman, is married to the Lady Teacher. 

So. D, the Salesman, is the grandfather of F. father of B and the husband of A. the Lady Teacher. 

A is the Lady Teacher 

Q is the son of R but R is not the mother. So, R is the Father of Q. P is married to R 

So, P is the wife of R and the mother of Q, X is the daughter of P and hence of R and so she is the Sister of Q, Y is the brother of R and Z is the brother of P. 

X is the sister of Q who is a male. So, Q is brother of X. 

Q is the son of R but R is not the mother. So, R is the Father of Q. P is married to R 

So, P is the wife of R and the mother of Q, X is the daughter of P and hence of R and so she is the Sister of Q, Y is the brother of R and Z is the brother of P. 

There are two females only — mother P and daughter X 

Q is the son of R but R is not the mother. So, R is the Father of Q. P is married to R 

So, P is the wife of R and the mother of Q, X is the daughter of P and hence of R and so she is the Sister of Q, Y is the brother of R and Z is the brother of P. 

Clearly, Q is the son of P and X is the daughter of P. So, P has two children. 

Q is the son of R but R is not the mother. So, R is the Father of Q. P is married to R

So, P is the wife of R and the mother of Q, X is the daughter of P and hence of R and so she is the Sister of Q, Y is the brother of R and Z is the brother of P. 

R is the father of Q 

D is father of A and grandfather of F. So, A is father of F. 

Thus, D and A are the two fathers. C is the sister of F So, C is the daughter of A. 

Since there is only one mother, it is evident that E is the wife of A and hence the mother of C and F. 

So, B is brother of A There are three brothers. So, F is the brother of C. 

Clearly, B and A are brothers. F is the brother of C So, three brothers are A, B, F. 

D is father of A and grandfather of F. So, A is father of F. 

Thus, D and A are the two fathers. C is the sister of F So, C is the daughter of A. 

Since there is only one mother, it is evident that E is the wife of A and hence the mother of C and F. 

So, B is brother of A There are three brothers. So, F is the brother of C. 

A, the father. is male B, the brother, is male, C, the sister, is female D, the grand-father, is male, E, the mother, is female F, the brother, is male. 

So, there are four males.