$A + B$ means $A$ is the daughter of $B$; $A \times B$ means $A$ is the son of $B$; and $A - B$ means $A$ is the wife of $B$.
If $P \times Q - S$,which of the following is true?

Pointing to a photograph,Sachin said,"She is the grandmother of my father's sister's son." How is the woman in the photograph related to Sachin?

$R$ is the daughter of $Q$. $M$ is the sister of $B$,who is the son of $Q$. How is $M$ related to $R$?

Anil introduces Rohit as the son of the only brother of his father's wife. How is Rohit related to Anil?

Read the following information carefully and answer the questions 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 $B$. Which of the following is a pair of females?

$A$ is the brother of $B$. $B$ is the brother of $C$. $D$ is the father of $A$. Based on these three statements,which of the following statements cannot be definitely true?