单选题 {{B}}Passage 2{{/B}}

Because humans are at the top of the food chain, they are particularly vulnerable to the effects of nondegradable (不可能降解的)pollutants. This was clearly illustrated in the 1950s and 1960s when residents living near Minamata Bay, Japan, developed nervous disorders, shaking, and paralysis(瘫痪，麻痹) in a mysterious widespread. Over 400 people died before authorities discovered that a local industry had released mercury(水银，汞) into Minamata Bay. This highly toxic element stored up in the bodies of local fish and eventually in the bodies of people who consumed the fish. More recently research has revealed that many chemical pollutants are harmful to the human beings.
Pollution also has a dramatic effect on natural resources. Ecosystems such as forests, wetlands, and rivers perform many important services for the earth's environment. They improve water and air quality, provide living places for plants and animals, and provide food and medicines. Any or all of these ecosystem functions may be impaired or destroyed by pollution. Moreover, because of the complex relationships among the many types of organisms and ecosystems, environmental pollution may have far-reaching consequences that are not immediately obvious or that are difficult to predict. For instance, scientists can only point out some of the potential impacts of the decrease of the ozone layer(臭氧层), the protective layer in the atmosphere that shields the earth from the sun's harmful rays.

单选题 The best title for this passage would be ______?

【正确答案】 B

【答案解析】可采用排除法。D项Pollutants(污染物)与整篇文章内容不符应排除。C项affect为一个动词，用在这儿是错误的，可以排除。在剩下的A、B两项中，A项强调污染；B项强调污染的影响。根据文章两段的主要侧重面来看还是强调影响，比如一段中人吃了受污染的鱼之后死亡；二段中臭氧层等等，讲的都是影响。

单选题 In the sentence "Because humans are at the top of the food chain, they are particularly vulnerable to the effects of nondegradable pollutants.", "vulnerable" probably means ______.

单选题 The "Minamata Bay" example in the first paragraph proved that ______.

A、 if mankind do something harmful to the environment, vice versa, the indeed victims are themselves
B、 a local industry which had released mercury into Minamata Bay was the real murderer
C、 how this highly toxic element stored up in the bodies of local fish and eventually harmful to the bodies of people who consumed the fish
D、 the theory of pollution

【正确答案】 A

【答案解析】根据文章的整体思想来做。文章的第—句话实际上是第一段的中心思想，(在27题已翻译过)。它强调的是人类若污染环境，反过来，自身是最大的受害者。而B、C项仅仅描述的是具体情况，没有站到文章的高度来深刻揭露内涵。