Read the following passage and write the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions from 28 to 32.

      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 do not approve of using nuclear power because it's 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.

(Adapted from sachmoi24h.com)

Question 28: Many people still believe that we will never _________ natural resources.

Question 29: According to the writer, we should use energy resources _________.

Question 30: The phrase "approve of” in the passage is closest in meaning to _________.

Question 31: What causes cancer and may badly affect the future generations?

Question 32: According to the passage, which of the following is NOT true about nuclear power?