Life gets noiser erery day and very few people can be free f

你说的是一片阅读理解吧?全文如下：
Life gets noisier every day and very few people can be free from noise of some sort or another.It doesn't matter where you live-in the middle of a modern city,or a faraway village-the chances are that you'll be disturbed by jet aeroplanes,transistor radios,oil-powered engines,etc.We seem to be getting used to noise,too.Some people feel quite lonely without background music while they're working.
Scientific tests have shown that total silence can be a very frightening experience for a human being.However,some people enjoy listening to pop music which is very loud,and this can do harm to their eardrums.The noise level in some discos is far above the usual safety level for heavy industrial areas.
One recent report about noise and concentration suggested that although a lot of people say that noise disturbs their concentration,what really influences their ability to concentrate is a change in the level of noise.It goes on to say that a background noise which doesn't change too much (music,for example) may even help people to concentrate.
原题为：
1.According to this passage,the noise pollution_____.
A.has become the worsr in the cities
B.has become better in the countries
C.has gone from cities to villages
D.has been heard everywhere in modern cities
2.What does background music refer to?It refers to_____.
A.music played while people are working
B.music used to help people to concenrtrate
C.noise that coninues while you're listening to other noises
D.music played in the backyard
3.Some people have their hearing harmed_____.
A.while listening to pop music
B.in total silence
C.when talking loudly
D.while watching TV
4.The reason that prevents people from concentrating on something is_____.
A.all kinds of noise
B.great changes in the level of noise
C.background noise
D.popular music
5.What may even let people concentrate?
A.Changeable noise.
B.Fairly stable noise.
C.Loud noise.
D.Some discos.
答案：CAABB