（3）处应填写（）

单项选择题By conducting an experiment, the American scientist tried to find out （）.

A．whether using aspirin would affect a person"s hearing ability
B．whether university students" hearing ability is better than others
C．how many Americans take great amounts of aspirin every day
D．why people face a serious danger of suffering hearing loss from loud noises

单项选择题If you place your questions in order of importance, you （）

A．put the least important first
B．put the longest question first
C．put the most important last
D．put the most important first