10.What will be the best title of the passage?

A. Ice Sheet in Greenland Melting at Alarming Speed

B. Greenland Ice Sheet Contributing to Rapid Sea Level Rise

C. Billions of Tons of Water Found under Greenland Ice Sheet

D. Scientists Predicting Massive Underground Water in Greenland

第二节（共5小题；每小题2分，满分10分）

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

　Do teenagers know how to sleep? If you're the parent of teens, you might be laughing to

yourself. That's all they know how to do. In truth, teens might not know enough about how to sleep, when to sleep and why. 11____

　Just as we focus on our diets and exercise for health, we need to consider sleep necessary

to our mental, physical and psychological health. "Good" sleep is sleep that is long enough to allow your brain to remove the side effects of daytime brain activity. Consistent bed and

wake-up times are the key to keeping our sleep cycles. 12___

　Teens are social creatures, and the most attractive social "gathering" place these days is on their digital devices. 13 Ideally, we should avoid blue light for at least half an hour before bed. But social media and homework that requires screen time mean too many kids are powering up their devices when their bodies should be powering down for the night.

　　___14__ Equally contributing to sleep issues are eating too late, taking naps, and failing to get enough exercise. In other words, these people have never learned how to sleep.

　　Over time, poor sleep leads to a decline in mood. _15__ Significantly, when I speak to my adult patients who are struggling with sleep issues, nearly all of them say their sleep problems started in high school.

Therefore, I recommend sleep education. Otherwise, we won't necessarily solve the health, safety and economic issues of sleepy teens.