云计算所具备的特性中，（）是指云计算可有效降低服务器的运维成本，平均每台服务器的运维人员数量不多于1个。

A.用户自助服务

B.资源共享

C.自动化管理

D.弹性扩展

Man: Brother! The guys next door are making so much noise. I can't focus on my homework. Woman: Why don't you go to the library, Tom It's much quieter there. Question: What does the woman imply

A．Tom should give up his homework.

B．Tom should shut the door.

C．Tom should do his homework at the library.

D．Tom should go and complain to his neighbors.