题目内容：

Doctors have known for a long time that extremely loud noises can cause hearing damage or loss. The noise can be the sound of a jet airplane or machines in factories of loud music or other common sound at home and at work. A person only needs to hear the noise for little more than one second to be affected.

An American scientist has found that using aspirin (阿斯匹林) increase the temporary（暂时的）hearing loss or damage from loud noise. He did an experiment using a number of students at a university who all had normal hearing. He gave them different amounts of aspirin for different periods of time, then he tested their hearing ability.        He found that students who were given four grams of aspirin a day for two days suffered much greater temporary hearing loss than those who did not use aspirin. The hearing loss was about two times as great.

The scientist said millions of persons in the U.S. use much larger amounts of aspirin than were used in his experiment. He said these persons face a serious danger of suffering hearing loss from loud noise.

1.Doctors have long known that              .

A．one may lose his hearing when he hears a terribly loud noise.

B．one may become deaf when he hears a loud noise.

C．loud noises can cause damage to the hearing of the young people only

D．common sounds at home are not harmful to the ear

2.One conclusion you can draw from the passage is that aspirin              .

A．makes hearing damage from loud noise worse

B．should never be taken more than four grams

C．can damage one’s hearing when it is given more than four grams daily

D．always increases hearing loss by two times

3.Millions of Americans are in danger of suffering hearing loss because they              .

A．take too much aspirin

B．often take air trips

C．like listening to loud music

D．have too much loud noises at home and at work

4.The American scientist did his experiment in order to find              .

A．how much aspirin would affect a person’s hearing

B．how much aspirin should be given in the treatment of the patients with hearing damage from loud noise

C．whether aspirin would increase the temporary hearing damage from loud noises

D．whether the people who had hearing damage should use aspirin