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】Management often decides to trade older trucks in for newer models rather than trying to repair them, and this process is more likely to occur in periods of high demand.