题目选项分析

For similar cars and comparable drivers, automobile insurance for collision damage has always cost more in Greatport than in Fairmont. Police studies, however, show that cars owned by Greatport residents are, on average, slightly less likely to be involved in a collision than cars in Fairmont. Clearly, therefore, insurance companies are making a greater profit on collisiondamage insurance in Greatport than in Fairmont.

In evaluating the argument, it would be most useful to compare

【选项】the level of traffic congestion in Greatport with the level of traffic congestion in Fairmont