In the global economy, a new drug for cancer, _________ it is discovered, will create many economic possibilities around the world. 

A．whatever

B．whoever

C．wherever

D．whichever

关于肺内压的生理意义，错误的是（）。

A.使肺保持扩张状态

B.使肺保持收缩状态

C.有利于肺通气

D.促进胸腔内静脉血和淋巴的回流

E.有利于肺换气