--How did he get infected?She the viruses without any protection.A. exposed toB. had ex

问题补充：

--How did he get infected?

--She the viruses without any protection.

A. exposed to

B. had exposed to

C. was exposed to

D. had been exposed

答案：

A. exposed to

B. had exposed to

(答案→)C. was exposed to

D. had been exposed

解析：试题分析：考查时态和语态。根据句意，表被动，排除A，B。根据上下文可知，是陈述过去的一个事实，故使用一般过去时。句意：——他是怎样感染的？——在没有任何保护的情况下面临病毒感染。