For similar cars and 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 collision-damage insurance in Greatport than in Fairmont.

Which of the following is an assumption on which the argument depends?

1. Repairing typical collision damage does not cost more in Greatport than in Fairmont.

2. There are no more motorists in Greatport than in Fairmont.

3. Greatport residents who have been in a collision are more likely to report it to their insurance company than Fairmont residents are.

4. Fairmont and Greatport are the cities with the highest collision-damage insurance rates.

5. The insurance companies were already aware of the difference in the likelihood of collisions before the publication of the police reports.

这道题的答案是A，是不是这样理解：虽然Greatport的保险公司的收费高，并且

Greatport的车辆事故发生率低，但是如果该地保险公司支付的赔偿金高，其利润不一定高。

但有一个常识性的问题不懂：难道赔偿金是根据车辆维修费用决定的吗？

请牛牛们指点

Your analysis is correct. Yes, the payment is based on the medical expense plus

the repaire cost caused by the accident. even though its assumption ignore the

medical expense as part of the total cost here.