根据短文内容，从下框的选项中选出能概括每一段主题的最佳选项，并在答题纸上将该选项涂黑，选项中有一项为多余选项。
A. Using a proverb to tell us how to keep healthy
B. Getting up early --- one good way to keep healthy
C. The importance of sleeping
D. Introduction to keeping healthy
E. The importance of the blood in our bodies
F. The benefit of exercise
__________
Habit is something we do very often. We do not think when we are doing it. We can have good habits or bad habits. This text gives some advice on how to be healthy. It tells you what to do if you want to be healthy. It also tells you what you must not do. It talks about good habits and bad habits.
_________
Early to bed and early to rise, makes a man healthy, wealthy and wise. This is an old English saying. Have you heard of it before? It means that we must go to bed early and get up early in the morning. if we do, we shall be healthy, we shall also be rich and clever.
________
Is this true? Perhaps it is. The body must have enough sleep .Children of your age need ten hours’ sleep every night. If you do not go to bed early, you can not have enough sleep. Then you can not think properly and you cannot do your work properly. You’ll not be wise and you may not become wealthy!
________
Some people go to bed late at night and get up late in the morning. This is not good for them. We must sleep at night when it is dark. The dark helps us to sleep properly. When daylight comes, we must get up. This is the time for exercise. Exercise means doing things with the body. Walking, running, jumping, swimming, playing games are all exercises. If the body is not used, it becomes weak. Exercise keeps it strong.
________
Exercise helps the blood to move around inside the body. This is very important. Blood takes food to all parts of our bodies. The brain in our heads also need blood. We think with our brains. If we keep our bodies healthy and take exercise, we can think well.