[求助]一道关于假定的逻辑题

A recent report determined that although only three percent of drivers on Maryland highways equipped their vehicles with radar detectors, thirty-three percent of all vehicles ticketed for exceeding the speed limit were equipped with them. Clearly, drivers who equip their vehicles with radar detectors are more likely to exceed the speed limit regularly than drivers who do not.

The conclusion drawn above depends on which of the following assumptions?

(A)    Drivers who equip their vehicles with radar detectors are less likely to be ticketed for exceeding the speed limit than are drivers who do not.

(B)     Drivers who are ticketed for exceeding the speed limit are more likely to exceed the speed limit regularly than drivers who are not ticketed.

这道题目是新东方的蓝皮书上册，P288的第14题，答案是B 但我觉得应该选A。

我的理解是：作者试图从装了雷达探测器的人有着不合比例高的罚单比例说明装了雷达探测器的人会比不装的人更多超速。这里就有一个假设，“装了雷达探测器可以降低开车人被吃罚单的概率”。然而这些人却有着不合比例高的罚单数，那就证明他们更常超速。因为如果没有这个假定，或者更夸张一些，这个假定变成“装了雷达探测器反而会增加开车人吃罚单的概率（虽然不合常理）”，那么那些装了雷达探测器的人有着不合比例高的罚单数，不是一件正常的事情了吗？这样就不能退出作者的结论。所以我觉得应该是A

麻烦请大家帮我看看，是不是我哪里钻了牛角尖。先谢谢了哈！