Many small roads do not have painted markings along their edges. Clear edge markings would make it easier for drivers to see upcoming curves and to judge the car’s position on the road, particularly when visibility is poor, and would therefore seem to be a useful contribution to road safety. However, after Greatwater
County painted edge markings on all its narrow, winding roads, the annual accident rate along those roads actually increased slightly. (E)
Which of the following, if true, most helps to explain the increase in accident rate? A. Greatwater
County has an unusually high proportion of narrow, winding roads. B. In bad weather it can be nearly as difficult for drivers to see the road as it is at night. C. Prior to the painting of the edge markings, Greatwater
County’s narrow, winding roads already had a somewhat higher accident rate than other Greatwater
County roads. D. Many of the accidents on narrow, winding roads involve a single vehicle veering off the road, rather than the collision of two vehicles. E. After the markings were painted on the roads, many drivers who had gone out of their way to avoid driving on those roads at night no longer did so.
答案给的是E 我选了D. 想不明白E怎么会造成increase。不是decrease吗？ | 
