1. (2022八上·昆明期中) 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答案。选项中有两项为多余选项

Everyone must go to bed early and get up early, or we can't be healthy and clever.

Is this true?The body must have enough sleep. Children need ten hours sleep every day.Then you can't think well and do your schoolwork well. You may not be clever.

Some people go to bed late and get up late. We must go to bed at night when it's dark(天黑). The dark helps us sleep well. When the daytime comes, we must get up. This is the time for exercise.

 If you don't exercise, you may be unhealthy. Exercise helps the blood(血液) flow around inside the body. This is very important. Blood takes food to each part of our body. If we keep our body healthy and take exercise, we can think better. 

A. If you don't go to bed early, you can't get enough sleep. B. Exercise keeps a strong body. C. Maybe it is. D. You can have a good sleep. E. This is not good for them. F. Some people exercise every day. G. The brain(大脑) also needs blood because we think with our blood.