Many people still believe that natural resources will never be used up. Actually, the world's energy resources are limited. Nobody knows exactly how much fuel is left. However, we also should use them economically and try to find out alternative sources of power. According to Professor Marvin Burnham of the New England Institute of Technology, we have to start conserving coal, oil and gas before it is too late; and nuclear power is the only alternative. However, many people don't approve of using nuclear power because it is very dangerous. What would happen if there were a serious nuclear accident ? Radioactivity causes cancer and may badly affect the future generations. The most effective thing is that we should use natural resources as economically as possible. 1. According to the passage, using nuclear power is ________. A. dangerous B. interesting C. safe D. cheap 2. Radioactivity from nuclear power ________. A. the future generations do nothing with it B. alters a new kind of energy C. are necessary to cure diseases D. causes cancer and has bad effect on the future generations 3. How much fuel is left ? A. No one knows exactly B. Let's use it as much as we would like C. It will never be used up D. There is a lot of fuel 4. We should use coal, oil and gas ________ A. as economically as possible B. carelessly C. as much as possible D. badly