单选题 Believe it or not, optical illusion can cut highway crashes.
Japan is a case in point. It has reduced automobile crashes on some roads by nearly 75 percent using a simple optical illusion. Bent stripes, called chevrons, painted on the roads make drivers think that they are driving faster than they really are, and thus drivers slow down.
Now the American Automobile Association Foundation for Traffic Safety in Washington D.C. is planning to repeat Japan"s success. Starting next year, the foundation will paint chevrons and other patterns of stripes on selected roads around the country to test how well the patterns reduce highway crashes.
Excessive speed plays a major role in as much as one fifth of all fatal traffic accidents, according to the foundation. To help reduce those accidents, the foundation will conduct its tests in areas where speed-related hazards are the greatest—curves, exit slopes, traffic circles, and bridges.
Some studies suggest that straight, horizontal bars painted across roads can initially cut the average speed of drivers in half. However, traffic often returns to full speed within months as drivers become used to seeing the painted bars.
Chevrons, scientists say, not only give drivers the impression that they are driving faster than they really are but also make a lane appear to be narrower. The result is a longer lasting reduction in highway speed and the number of traffic accidents.

单选题 The passage mainly discusses ______.

单选题 On roads painted with chevrons, drivers tend to feel that ______.

【正确答案】 C

【答案解析】[解析] 本题答案可定位在第二段最后一句话“Bent stripes... and thus drivers slow down.”，think和feel属于关键词替换，think后面就是答案：认为他们开的比实际速度要快，然后会慢下来。故选C。

单选题 The advantage of chevrons over straight, horizontal bars is that the former ______.

【正确答案】 C

【答案解析】[解析] 从文章最后一段的最后一句可知，人字形线能较长期降低汽车在公路上的行驶速度和减少交通事故的次数。而且第五段最后一句说“However, traffic often returns to full speed within months as drivers become used to seeing the painted bars.”(然而，往往几个月后车辆又恢复全速，因为司机已习惯看到那些横线)。两者比较，人字形的影响时间更长，所以选C。