Deepika tells Shraddha,"Your mother's father's son is the husband of my sister." How is Deepika related to Shraddha?

Read the following information carefully and answer the question given below. 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?

Pointing to a person,a man said to a woman,'His mother is the only daughter of your father'. How was the woman related to the person?

$A$ is the son of $B$. $C$,$B$'s sister,has a son $D$ and a daughter $E$. $F$ is the maternal uncle of $D$. How many nephews does $F$ have?

$P$ is the son of $Q$,while $Q$ and $R$ are sisters. $T$ is the mother of $R$. If $S$ is the son of $T$,which of the following statements is correct?

Pointing to a boy,Seema said,"He is the son of my grandfather's only child". How is the boy related to Seema?