题目内容：

    New data presented this week at the annual Associated Professional Sleep Societies (APSS) suggest that a student's preferred sleeping schedule has a lot to do with his or her grade-point average in school. In one study, researchers at the University of Pittsburg revealed that poor sleep habits among high schoolers led to lower grades, particularly in math.

It's no surprise that poor sleep habits may negatively impact academic performance. And dozens of studies have linked an increase in nightly sleep to better cognition and alertness. The new research, however, goes a step further, quantifying the impact of erratic or inadequate sleep on grades. These findings are more convincing than saying that if you get more sleep, you'll feel better," says Jennifer Cousins, a lead researcher of the study.

The study involved data from 56 adolescents (34 female) between the ages of 14 and 18 years. They were asked to fill out sleep diaries for one week and wear a special activity monitor on their wrists, which recorded when the students were asleep or awake. Overall, teens with poor sleep habits received lower grades than students who stuck with a more regular sleep routine.

Interestingly, Cousins also found that different sleep habits had different effects on the students' school performance：those who woke up more often during the night did worse in math, for example, while those who slept peacefully through the night tended to get better grades in English.

These findings bring up new questions about teasing out（探讨）the details of what is important about sleep that impacts learning," says Cousins. "Does more sleep improve our ability to deal with abstract concepts found in math, or does sleep quality increase creativity? We don't know the answers, and don't want to draw those conclusions yet. But this helps us understand more about how sleep helps the things we do in daily life. "

Authors of the study point out that the results provide overwhelming evidence of the importance of sleep during a period of development that is critical for adolescents and recommend sleep education as a prevention tool to help increase awareness of the importance of sleep and of the negative consequences of poor sleep.

1.The underlined word "erratic" in the second paragraph probably means______.

A.adequate B.different

C.stable D.irregular

2.We can learn from Jennifer Cousins' research that_____.

A.lower grades in math are related to more awakenings at night

B.the longer you sleep, the better your grades in English will be

C.the findings will cause new insoluble problems about sleeping and learning

D.different sleep habits have similar effects on students' learning

3.Which of the following do you think Jennifer Cousins will NOT agree with?

A.People should understand the importance of sleep for students.

B.Whether greater sleep quality help increase students' creativity is not known yet.

C.Students' grades mainly depend on their sleep quality.

D.The study helps researchers understand how sleep affects learning.

4.Which of the following would be the best title for the passage?

A.The More Sleep, the Better Cognition

B.The Poorer Sleep Habits, the Lower Grades

C.The More Sleep, the Better You Will Feel

D.The More Peacefully You Sleep, the Higher Grades You Will Get