—How did she get infected?

—She _______ the viruses without any protection．

A．exposed to

B．had exposed to

C．was exposed to

D．been exposed to

妊娠期急性阑尾炎的特点是()

A．穿孔率高

B．大网膜难以包裹炎症的阑尾

C．肌紧张不明显

D．炎症不易局限

E．压痛位置常较高