题目内容：

    You may know about “junk food” like hamburgers. But do you know about “junk sleep” ?

A British survey found that electronic products(电子产品) in teenagers' bedrooms are affecting(影响) their sleep.

The survey was among(在……之间) 1,000 British children between 12 and 16. It found that 30% of them got just 4 to 7 hours of sleep every day. But doctors say they need 8 to 9 hours.

Almost 25% of the kids said they fell asleep more than once a week while watching TV, listening to music or using other electronic products.

“This is very worrying,” said Dr.Chris Idzikowski, a British expert. “We call it ‘junk sleep’. It means you don't get enough sleep and the quality(质量) of the sleep is bad, too. If you don't get a good rest, you won't perform well in school the next day.”

The survey found that 40% of the kids felt tired each day, with girls between 13 and 16 feeling the worst. Nearly all the teenagers have a phone, an MP4 or a TV in their bedrooms. And many of them have all three.

1.This passage is mainly about ________.

A.junk food B.junk sleep

C.the importance of sleep D.electronic products

2.________ of the children in the survey sleep only 4 to 7 hours a day.

A.200 B.300 C.500 D.1，000

3.“Junk sleep” means ________.

A.people don't have enough sleep B.the quality of the sleep is good

C.people don't like sleeping D.people have enough sleep

4.Which of the following is TRUE according to the passage?

A.Teenagers need 4 to 7 hours of sleep each day.

B.Few teenagers have a phone in their bedrooms.

C.Teenagers spend too much time on electronic products.

D.Girls between 15 and 16 spend the least time on electronic products.