单选题

　　1.【概括大意】Our bodies are estimated to be about 60 to 70% water. Blood is mostly water, and our muscles, lungs, and brain all contain a lot of water. Water is needed to regulate body temperature and to provide the means for nutrients (滋养) to travel to all our organs. Water also transports oxygen to our cells, removes waste, and protects our joints and organs.

　　The main idea of this paragraph is__________.

　　A.Ounces of Water Needed Per Day

　　B.Importance of Water

　　C.Water in Our Body

　　D.The Function of Water