Which one of the follow ing options is a tautology?

A

$$(\sim Q \rightarrow \sim P) \vee Q$$

B

$$(P \wedge Q) \rightleftharpoons (\sim P \vee \sim Q)$$

C

$$\sim (P \vee Q) \vee (\sim P \wedge Q) \vee P$$

D

$$(P \vee Q) \wedge (\sim P \vee \sim R)$$