Passage Three
When Iraqi troops blew up hundreds of Kuwaiti oil wells at the end of the Gulf War, scientists feared an environmental disaster. [33]Would black powder and the smoke from the fires circle the globe and block out the sun? Many said "No way. Rain would wash the black powder from the atmosphere." But in America, air-sampling balloons have detected high concentrations of particles similar to those collected in Kuwait. Now that the fires are out, scientists are turning attention to yet another threat-the oil did not catch fire. It has formed huge lakes in the Kuwaiti deserts. They trap insects and birds and poison a variety of other desert animals and plants. [34]The only good news is that the oil lakes have not affected the underground water resources. So far, the oil has not been absorbed because of the hard sand just below the surface.
Nothing, however, stops the oil from evaporating. The resulting poisonous gases are choking nearby residents. [35]Officials are trying to organize a quick clean-up, but they are not sure how to do it. One possibility is to burn the oil. Get those black powder detectors ready.

Questions 33 to 35 are based on the passage you have just heard.
33. What were the scientists worried about soon after the Gulf War?
正确答案：D
解析：题目询问海湾战争结束之后不久，科学家们担心什么。关键是要听到“大火产生的黑色粉末和烟会不会环绕全球并遮挡住太阳呢？”可知D为答案。符合短文听力“听到什么选什么”的原则。选项A、B、C的内容文中均未提及。
34. What was the good news for scientists?
正确答案：D
解析：题目询问对于科学家们来说，好消息是什么。关键是要听到“唯一的好消息是，石油形成的湖泊尚未污染地下水资源。”D是原文的同义表达。A错在oil；文中说石油毒死了许多沙漠动植物，故B不正确。文中说因为地层下面有坚硬的沙，迄今为止石油仍未被吸收；什么都无法阻止石油的蒸发，故C不正确。
35. What are the officials trying to do at the moment?
正确答案：C
解析：题目询问目前官员们正试图做些什么。关键是要听到“官员们正试图组织一次快速的清洁行动”，C是原文的同义表达。