—Let’s go to the concert this evening.It’s said to be excellent.

—I’d like to,but I have something to do.

—_________!It is the last time.We’ll have no chance to enjoy it.

A．What a pity

B．Not at all

C．All the best

D．Never mind

放射敏感性与可治愈性的关系（）。

A.等于可治愈性

B.不等于可治愈性，但两者有关系

C.与可治愈性无关

D.与可治愈性关系不大

E.以上说法均不对