题目内容：

    How often do you exercise? A new study found that most kids aged 12 to 15 weren't getting enough physical activity. The results were based on about 800 kids. As part of the study, the kids tracked and reported on their own activity levels, and took physical exams.

U. S. fitness guidelines suggest an hour or more of physical activity every day. According to the study, only 1in 4 U.S. kids get enough physical activity.

"It's certainly worrying to see that our kids have such a limited amount of physical activity each day,” said Dr. Stephen Pont. He is an expert on children's health.

Few kids in the study met the guidelines on physical activity that raises the heart rate and makes people breathe harder. Overall, about 25% said they got an hour of that kind of exercise every day. Kids also reported on which activities they did most often outside of school gym class--basketball for boys and running for girls.

The study found that fat teenagers were less active than normal-weight girls and boys. Fat girls were slightly less active than normal-weight girls, but levels were similar among overweight and normal-weight boys. The study also said that the percent of fat children aged 2 to 19 was 17%, or about 12.5 million kids.

"There's always room for improvement," said Tala Fakhouri, who was the leader of the study. She also said the results provide useful information to help with fitness campaigns such as Let's Move, which was initiated by Michelle Obama in 2010. To inspire kids to eat right and get in shape, Michelle visits schools and holds exercise events. She also calls on schools to offer regular gym classes.

The study also found kids who get physical education at school may get better grades.

1.What is the result of the new study?

A. 800 kids don't get enough physical activity.

B. Most U.S. kids don't get enough exercise.

C. Kids should get physical activity every day.

D. It's important to take physical exams.

2.Which of the following sports do girls like best?

A. Swimming. B. Basketball. C. Running. D. Gym.

3.What's the purpose of the campaign Let's Move?

A. To help kids to keep fit. B. To provide useful information.

C. To offer regular gym classes. D. To hold exercise events.

4.According to the study children with enough exercise may__________.

A. be less active than fat children B. be more willing to help others

C. do better in their studies D. try their best to get in shape