题目选项分析

When there is a high demand for a trucking company's services, more money is spent on vehicle maintenance and safety inspections than at other times. Thus, the rate of truck accidents should be lower when there is high demand for the company's services than when demand is lower and less money is spent on vehicle maintenance and safety inspections.

Which of the following, if true about a truck company when there is a high demand for its services, casts the most serious doubt on the conclusion drawn above?

【选项】If all drivers within a given division of the trucking company achieve a perfect safety record for an entire quarter, each driver receives a five percent salary increase.