军团菌主要是通过哪种途径进入人体（）。

A.呼吸道

B.消化道

C.皮肤

D.消化道和呼吸道

E.皮肤和消化道

---I was trying to carry out the plan, but I failed.

---Well, you _____, for we were uncertain it would do ____.

A．needn’t do that, in fact

B．needn’t have done, in effect

C．needn’t have, in practice

D．needn’t, in time