根据短文内容，选择恰当的句子把短文补充完整。注意选项中有一个多余选项。
Of all the things we eat and drink, water is the most important. Not many people realize this, but it is quite true.    小题1:  , but two or three days without water usually leads to death. Many people do not understand how much water the human body needs at work and many people do not drink enough especially in cold weather.    小题2:  . Most people drink when they are thirsty, but we often need more water, especially after doing exercise.
___小题3:  . Water is very important in several different ways. Most people need about five to seven liters of water every day, but we do not need to drink that amount, because a lot of water comes from the food we eat.    小题4:  , however, we feel tired and may become ill. 

A. If we do not have enough water B. A man’s body contains 65% --- 75% water C. Most people drink enough only in hot weather D. We need to drink water before doing exercise E. The human body can live without food for a long time