$K$ 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 $A * B$ means $A$ is the mother of $B$; $A + B$ means $A$ is the brother of $B$; $A \times B$ means $A$ is the son of $B$ and $A - B$ means $A$ is the daughter of $B$,which of the following means $C$ is the niece of $D$?

Following questions are based on the information provided below:
$A \times B$ means $A$ is mother of $B$.
$A - B$ means $A$ is brother of $B$.
$A + B$ means $A$ is sister of $B$.
$A \div B$ means $A$ is father of $B$.
How is $K$ related to $M$ in $R \div M - K$?

$A \div B$ means $A$ is the father of $B$,$A - B$ means $A$ is the wife of $B$,$A \times B$ means $A$ is the brother of $B$,$A + B$ means $A$ is the daughter of $B$.
If $P \times R \div Q$,which of the following is true?

Pointing to a lady,Rajan said,"She is the daughter of the woman who is the mother of the husband of my mother." Who is the lady to Rajan?

$A$ is the father of $C$. But $C$ is not his son. $E$ is the daughter of $C$. $F$ is the spouse of $A$. $B$ is the brother of $C$. $D$ is the son of $B$. $G$ is the spouse of $B$. $H$ is the father of $G$. Who is the grandmother of $D$?