Most of the world's supply of uranium currently comesfrom mines. It is possible to extracturanium from seawater, but the cost of doing so is greater than the price thaturanium fetches on the world market. Therefore, until the cost of extracting uranium from seawater cansomehow be reduced, this method of obtaining uranium is unlikely to becommercially viable.

　　Which of the following would it be most useful todetermine in evaluating the argument?

　　(A) Whether the uranium in deposits on land is rapidlybeing depleted

　　(B) Whether most uranium is used near where it is mined

　　(C) Whether there are any technological advances thatshow promise of reducing the cost of extracting uranium from seawater

　　(D) Whether the total amount of uranium in seawater issignificantly greater than the total amount of uranium on land

　　(E) Whether uranium can be extracted from freshwater at acost similar to the cost of extracting it from seawater

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