[解析]
(1)C 细节理解题.根据文章第一段"We didn't know at that time there even was an environment,let alone that there was a problem with it,"says Bruce Anderson,president of Earth Day USA.可知在1970年世界地球日开始的时候,人们甚至都不知道有"环境"这个词,更不要说知道存在着环境问题了.故选C.
(2)A 细节理解题.根据文章第二段Business people,political leaders,university professors,and especially millions of grass﹣roots Americans are taking part in the movement.商务人士、政治领袖、大学教授,尤其是基层的数以百万计的美国人都参加了运动,可知环境保护的主要支持来自于普通民众.故选A.
(3)D 推理判断题.根据第三段According to US government reports,emissions (排放)from cars and trucks have dropped from 10.3 million tons a year to 5.5 tons.The number of cities producing CO beyond the standard has been reduced from 40 to 9.可知通过人们的共同努力,现在的污染排放的数字已经大大地减少了,故选D.
(4)A 推理判断题.根据文章最后一段Twenty﹣five years ago,there were hardly any education programs for environment.Today,it's hard to find a public school,university,or law school that does not have such a kind of program.可知现在几乎每个学校都有关于环境保护方面的教育的内容.说明教育在环境保护方面有很重要的作用.故选A.