The negation of $$(p \rightarrow q)\rightarrow r$$ is

A

$$(p \rightarrow r) \wedge (q\rightarrow r)$$

B

$$(\sim p \rightarrow r) \wedge (q\rightarrow r)$$

C

$$(p \rightarrow r) \wedge (\sim q\rightarrow r)$$

D

$$(\sim p \rightarrow r) \wedge (\sim q\rightarrow r)$$