阅读理解 One in five US teenagers have some

问题：

阅读理解

     One in five US teenagers have some degree of hearing loss,  according to researchers who said the

problem is growing."Teenagers really underestimate how much noise they are exposed to" Dr Josef

Shargorodsky said.__①__

     The study,  published in the Journal of the American Medical Association,  compared national surveys between the early 1990s and the mid2000s.In the first survey,  about 15 percent of teenagers had some

degree of hearing loss.__②__Most of the hearing loss was in one ear only.While it was usually slight, 

 one in 20 adolescents had more pronounced (显著的) problems-up 50 percent since the first survey.

     Hearing loss is very common in the elderly,  Grimes said,  but she added that it was concerning to see

it come into the younger age groups.In babies and young children,  hearing problems are known to delay

language development,  which in turn influences performance in other areas.Slight hearing loss,  for instance,  makes it difficult to distinguish between highfrequency consonants like "s" and "f"

__③__The science is less clear for adolescents,  but it is easy to imagine how being hard of hearing could

influence learning,  said Grimes."We know from a lot of data that noisy classrooms are one of the biggest

challenges to learning."

     The reasons for the rise are still uncertain.When asked about noise exposure-on the job,  from

firearms or recreational activities,  for instance-the teenagers didn't indicate any change.But Shargorodsky said,  "We knew from before that it is difficult to ask this age group about noise exposure-they

underestimate it."__④__Although it's not clear that these devices are to blame,  Grimes said it was still a

good idea to turn down the volume.But she pointed out the advice would likely fall on deaf ears.She said

the American Academy of Hearing had also contacted Steve Jobs,  the CEO of Apple,  about adding a

volume limiter on iPods,  but never heard back.

1. In which place should the sentence "Few people would call it noise when they listen to music on their

    MP3 players,  for instance." be put?

A. ①  

B. ②  

C. ③  

D. ④

2. What's the main idea of the third paragraph?

A. Hearing loss was very common in the elderly in the country.

B. The sounds like "s" and "f" are hard to distinguish by babies.

C. The number of teenagers with hearing problems is decreasing.

D. Babies and teenagers are also facing problems of hearing loss.

3. Which of the following is TRUE?

A. The reasons of the hearing loss are known to the researchers.

B. The surveys have been carried out for at most 15 years.

C. The reasons for the rise are clear to the researchers.

D. The results of the surveys have been published in a newspaper.

4. The American Academy of Hearing contacted the CEO of Apple in order to________.

A. share the surveys with the CEO of Apple

B. get more help in finance from the Apple Company

C. remind the company to add a volume limiter on iPods

D. express warning and threat to the CEO of Apple