Pointing to a man on the stage,Rita said,"He is the brother of the daughter of the wife of my husband." How is the man on the stage related to Rita?

In a family,there are six members $A, B, C, D, E$ and $F$. $A$ and $B$ are a married couple,$A$ being the male member. $D$ is the only son of $C$,who is the brother of $A$. $E$ is the sister of $D$. $B$ is the daughter-in-law of $F$,whose husband has died.
How is $E$ related to $C$?

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 $B$.
Which of the following is a pair of females?

$Q$ is the brother of $R$; $P$ is the sister of $Q$; $T$ is the brother of $S$; $S$ is the daughter of $R$. Who are the cousins of $Q$?

$A$ girl introduced a boy as the son of the daughter of the father of her uncle. The boy is the girl's:

$I.$ $A, B, C, D, E$ and $F$ are six members of a family.
$II.$ One couple has parents and their children in the family.
$III.$ $A$ is the son of $C$ and $E$ is the daughter of $A$.
$IV.$ $D$ is the daughter of $F$ who is the mother of $E$.
Which of the following pairs are the parents of the children?