Many small roads do not have painted markings along theiredges. Clear edge markings would make iteasier for drivers to see upcoming curves and to judge the car's position onthe road, particularly when visibility is poor, and would therefore seem to bea useful contribution to road safety. However, after Greatwater County painted edge markings on all itsnarrow, winding roads, the annual accident rate along those roads actuallyincreased slightly.

　　Which of the following, if true, most helps to explainthe increase in accident rate?

　　(A) Greatwater County has an unusually high proportion ofnarrow, winding roads.

　　(B) In bad weather it can be nearly as difficult fordrivers 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 higheraccident rate than other Greatwater County roads.

　　(D) Many of the accidents on narrow, winding roadsinvolve a single vehicle veering off the road, rather than the collision of twovehicles.

　　(E) After the markings were painted on the roads, manydrivers who had gone out of their way to avoid driving on those roads at nightno longer did so.

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