新美国GRE阅读完全剖析（三）(2)

　　28. The passage is structured to lead to which of the following as a conclusion?

　　A. The use of biodiesel will increase by less than one percent over the next 15 years.

　　B. During the next 15 years, the production of biodiesel will be increased as fast as it is possible to increase it.

　　C. During the next 15 years, it will be impossible, just by switching to biodiesel, to meet the government's stated goal with respect to reducing air pollution.

　　D. Fifteen years from now, the air pollution caused by the production and use of one gallon of regular diesel fuel will be far less than it currently is.

　　E. There will be no significant year-to-year increase in the amount of regular diesel fuel used during the next 15 years.

　　全文给出了很多细节性的数字，而解题需要对相关数字做出简单推算。可以设现在每加伦传统diesel油的污染x，现在一年需要消耗的油量y加伦。简单估算后，产量严重限制了最后biodiesel最后对减少污染的实际作用，所以正确答案为C。A选项混淆了产量和使用情况;B选项与原文末句叙述不符;D选项比较的是一加仑现在使用的diesel油与15年后污染情况;E选项比较具有迷惑性，但是核心主体为diesel，而不是文中的biodiesel。