听下面一段材料, 回答第1-3题。 1. Where does the fresh water people need come from? [ ] A. Rivers and lakes. B. Underground. C. Both A and B. 2. How much water can we drink of all the water in the world? [ ] A. 3%. B. 4%. C. 97%. 3. What is the speaker mainly talking about? [ ] A. The ways of getting fresh water. B. How to use fresh water in our daily life. C. How the rivers are polluted.