题目选项分析

In the nation of Partoria, large trucks currently have a much higher rate of traffic accidents per mile driven than other vehicles do. However, the very largest trucks—those with three trailers—had less than a third of the accident rate of single- and double-trailer trucks. Clearly, therefore, one way for Partoria to reduce the number of traffic accidents would be to require shippers to increase their use of triple-trailer trucks.

Which of the following, if true, most seriously weakens the argument?

【选项】The volume of truck traffic on Partoria's highways could be reduced by encouraging shippers to use rail transport whenever possible.