A、To tell a story. B、To give advice. C、To provide facts. D、To compare opinions. B短文通过列出孩子发胖的三个原因，最后给出建议：鼓励孩子多运动，让他们远离快餐店和不良的饮食习惯

Many facts suggest that children are overweight and the situation is getting worse, according to doctors. I feel there are a number of reasons for this.
    Some people blame the fact that we are surrounded by shops selling unhealthy, fatty foods, such as fried chicken and ice cream, at low prices. This has turned out a whole generation of grownups who seldom cook a meal for themselves. If there were fewer of these restaurants, then probably children would buy less take-away food.
    There is another argument that blames parents for allowing their children to become overweight. I agree with this, because good eating habits begin early in life, long before children start to visit fast food shops. If children are given fried chicken and chocolate rather than healthy food, or are always allowed to choose what they eat, they will go for sweet and salty foods every time, and this will carry on throughout their lives.
    There is a third reason for this situation. Children these days take very little exercise. They do not walk to school. When they get home, they sit in front of the television or their computers and play computer games. Not only is this an unhealthy pastime, it also gives them time to eat more unhealthy food. What they need is to go outside and play active games or sports.
    The above are the main reasons for this problem, and therefore we have to encourage young people to be more active, as well as steer them away from fast food shops and bad eating habits.
Questions 23 to 25 are based on the passage you have just heard.
23. What kind of children may eat more unhealthy food according to the passage?
24. Why does the speaker think that children are becoming overweight?
25. What is the main purpose of the passage?