A、To cure diarrhea. B、To kill harmful bacteria. C、To clear harmful bacteria. D、To keep fluid levels normal. D第四段指出the mixture不能治

Forty thousand of the world’ s young children die every day. This is 15 million a year. Many of these deaths can be prevented. In fact, experts say techniques now exist to save the lives of half of these children. The techniques are medically effective, simple to use and low-cost. The biggest task has been to inform parents about these life-saving techniques.
    The United Nations Children’ s Fund lists four ways to improve children’ s health. The first way is to use a mixture of sugar, salt and water to treat diarrhea.
    Diarrhea is the major cause of death among children in developing countries. Diarrhea results when the body tries to clear itself of harmful bacteria. The body does this by expelling fluids, sometimes uncontrollably, from the bowels. If too much water, sugar and salt are lost in this way, the kidneys and heart cannot work normally. The child may die.
    This diarrhea treatment uses a simple mixture of sugar and salt in water. The mixture does not stop diarrhea. But if used as often as needed, it keeps fluid levels normal until the body has fought off the harmful bacteria.
    You can make the mixture with the sugar, salt and water you use every day. A local health care worker can teach you how to prepare it.
    The treatment has worked successfully in many countries. In Egypt, for example, the treatment was used in a children’ s health care program in the province of Alexandria. It reduced by one-half the number of deaths caused by diarrhea. The program has now been extended throughout Egypt.
21. How many young children die every year in the world?
22. How many ways does The United Nations Children’ s Fund list to improve children’ s health?
23. Why does diarrhea endanger children’ s lives?
24. What is the function of the mixture?
25. Which is not true about the treatment?