$K$ is the brother of $N$ and $X$. $Y$ is the mother of $N$ and $Z$ is the father of $K$. Which of the following statements is not definitely true?

If $X \circ Y$ means $X$ is the wife of $Y$,$X \cdot Y$ means $X$ is the son of $Y$,and $X * Y$ means $X$ is the sister of $Y$,which of the following would mean that $A$ is the daughter of $B$?

Pointing to a lady,a girl said,"She is the daughter-in-law of the grandmother of my father's only son." How is the lady related to the girl?

There is a family of six persons $A, B, C, D, E,$ and $F$. They are Lawyer,Doctor,Teacher,Salesman,Engineer,and Accountant. There are two married couples in the family. $D$,the Salesman,is married to the Lady Teacher. The Doctor is married to the Lawyer. $F$,the Accountant,is the son of $B$ and brother of $E$. $C$,the Lawyer,is the daughter-in-law of $A$. $E$ is the unmarried Engineer. $A$ is the grandmother of $F$. What is the profession of $B$?

All the six members of a family $A, B, C, D, E$ and $F$ are travelling together. $B$ is the son of $C$ but $C$ is not the mother of $B$. $A$ and $C$ are a married couple. $E$ is the brother of $C$. $D$ is the daughter of $A$. $F$ is the brother of $B$.
How many children does $A$ have?

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 $A$?