If P + Q means that P is the mother of Q, P ÷ Q means that P is the father of Q, P - Q means that P is the sister of Q, then which of the following expression shows that A is the maternal grandfather of C?

A

$$B \div A + C$$

B

$$A - B \div C$$

C

$$A + B \div C$$

D

$$A \div B + C$$