这道题答案没有问题，是排除法得到的，总觉得选项A的推理不足以作为assumption，但没有更好的选项，不知大家是怎么想的？
For similar cars and drivers, automobile insurance for collision damage has always cost more in Greatport than in LACE w:st="on">FairmontLACE>. 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 LACE w:st="on">FairmontLACE>. Clearly, therefore, insurance companies are making a greater profit on collision-damage insurance in Greatport than in LACE w:st="on">FairmontLACE>.
Which of the following is an assumption on which the argument depends?
- Repairing typical collision damage does not cost more in Greatport than in LACE w:st="on">FairmontLACE>.
- There are no more motorists in Greatport than in LACE w:st="on">FairmontLACE>.
- Greatport residents who have been in a collision are more likely to report it to their insurance company than Fairmont residents are.
- Fairmont and Greatport are the cities with the highest collision-damage insurance rates.
- The insurance companies were already aware of the difference in the likelihood of collisions before the publication of the police reports.
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