Pointing to a lady,a man said,'The son of her only brother is the brother of my wife'. How is the lady related to the man?

$A$ is the father of $X$; $B$ is the mother of $Y$. The sister of $X$ and $Z$ is $Y$. Which of the following statements is definitely not true?

$A$ 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 the grandfather of $R$ and is a contractor. $S$ is the grandmother of $T$ and is a housewife. There is one doctor,one contractor,one nurse,one housewife,and two students in the family. Which of the following are the two married couples?

Daya has a brother,Anil. Daya is the son of Chandra. Bimal is Chandra's father. In terms of relationship,what is Anil to Bimal?

Five persons namely $P, Q, X, Y,$ and $Z$ are sitting in a park. $P$ is the mother of $X$,who is the wife of $Z$. $Y$ is the brother of $P$,and $Q$ is the husband of $P$. How is $P$ related to $Z$?

$P + Q$ means $P$ is the brother of $Q$; $P - Q$ means $P$ is the mother of $Q$; and $P \times Q$ means $P$ is the sister of $Q$. Which of the following means $M$ is the maternal uncle of $R$?