24-37 Fish currently costs about the same at seafood stores throughout Eastville and its surrounding suburbs. Seafood stores buy fish from the same wholesalers and at the same prices, and other business expenses have also been about the same. But new tax breaks will substantially lower the cost of doing business within the city. Therefore, in the future, profit margins will be higher at seafood stores within the city than at suburban seafood stores.

For the purpose of evaluating the argument, it would be most useful to know whether

A) more fish wholesalers are located within the city than in the surrounding suburbs.

B) any people who currently own seafood stores in the suburbs surrounding Eastville will relocate their businesses nearer to the city

C) the wholesale price of fish is likely to fall in the future

D) fish has always cost about the same at seafood stores throughout Eastville and its surrounding suburbs.

E) Seafood stores within the city will in the future set prices that are lower than those at suburban seafood stores.

the referenced answer is E, however, i still have difficult in reasoning by this way. My choice is D.

虽然题目说了，buy fish from the same wholesalers and at the same price, 但是并没有说以后也是这样啊？（有点钻牛角尖）。可是觉得E也不对，因为既然taxbreak will substantially lower the cost of doing business within the city,就算seafood store within the city will set the prices lower or higher, profit margin 还是会高啊？profit margin = revenue - cost. cost 减少substantially，不管price/revenue高还是低，都会导致profit margin升高啊。

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