HELP! 一道不会的prep逻辑

轩辕亦舒

In the two years following the unification of Germany in 1989, the number of cars owned by residents of East Germany and the total distance traveled by cars in East Germany both increased by about 40 percent.In those two years, however, the number of East German residents killed each year as car occupants in traffic accidents increased by about 300 percent.

Which of the following, if true, most helps to explain the disproportionate increase in traffic fatalities?

(A) The average number of passengers per car was higher in the years before unification than it was in the two years after.

(D) Drivers who had driven little or not at all before 1989 accounted for much of the increase in the total distance traveled by cars

答案是D  怎么想也不可能啊 没有解释题目中最后一句话，也就是为什么死亡率增加了那么多啊~~~~

不胜感激！！！

轩辕亦舒

各位帮帮忙啊。。。

amy虫子

A是说在unification之前车上的乘客比之后的乘客多
无关项，即使是之后比之前多也没用，文章是说car occupants （车主） in traffic accidents increased by about 300 percent，
D项说在所有的行程中，那些1989之前不开或很少开的人（那就是新手咯）占的比重上升了很多