What reason do Americans give for the reduction in traffic accidents? A．Their imposition of speed limit. B．Their introduction of driving tests. C．Their guide to inexperienced drivers. D．The rise in their traffic density.
A.Their B. B．Their C. C．Their D. D．The E.
【参考答案】
D 题干中的专有名词Americans提示我们在第四段中。第四段指出：然而，在美国，人们认为交通事故的减少归因于......