In the nation artoria,large trucks currently account for 6 percent of miles driven on Partoria's roads but are involved in 12 percent of all highway fatalities.The very largest trucks -------those with three trailers -------had less than a third of accident rate of single-and-double-trailer trucks.Clearly,therefore,one way for Partoria to reduce highway deaths would be to require shippers to increase their use of triple-trailer trucks. Which of the following,if true ,most seriously weakens the argument? A.Partoria trucking companies have so far used triple-trailer trucks on lightly traveled sectio of major highways only. C.Very few fatal collissions involving trucks in Partoria are collissions between two trucks. 答案给的是A,可A什么意思啊,怎么就削弱了呢?我选的是C,我觉得更有可能啊,很少有事故涉及到两卡车,那就换任何 trailer也没用啊,有可能是其他车型所造成的,而非truck,希望高手们能解决一下,谢谢。 |