Pointing to a photograph,a man tells his friend,'She is the daughter of the only son of my father's wife'. How is the girl in the photograph related to the man?

If,$(A)$ $P + Q$ means $P$ is the brother of $Q$,$(B)$ $P \times Q$ means $P$ is the father of $Q$,$(C)$ $P - Q$ means $P$ is the sister of $Q$,which of the following represents $S$ is the niece of $T$?

$A + B$ means $A$ is the son of $B$; $A - B$ means $A$ is the wife of $B$; $A \times B$ means $A$ is the brother of $B$; $A \div B$ means $A$ is the mother of $B$; and $A = B$ means $A$ is the sister of $B$.
What does $P = R + Q$ mean?

$P + Q$ 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 $R$?

$A + B$ means $A$ is the son of $B$; $A - B$ means $A$ is the wife of $B$; $A \times B$ means $A$ is the brother of $B$; $A \div B$ means $A$ is the mother of $B$; and $A = B$ means $A$ is the sister of $B$.
What does $P = R + Q$ mean?

Given that:
$1.$ $A$ is brother of $B$.
$2.$ $C$ is father of $A$.
$3.$ $D$ is brother of $E$.
$4.$ $E$ is daughter of $B$.
Then,uncle of $D$ is