[备考心经] 求问一道逻辑题目~~~~

Most of the world’s supply of uranium currently comes from mines.It is likely to extract uranium for seawater .However, the cost of doing so is higher than the price that fetches on the world market. Thus, until the cost of extracting uranium from seawater can somehow be decreased, this method of obtaining uranium is not likely to be commercially viable.

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

A  Whether the uranium in deposits on land is rapidly being depleted.

C.  Whether there are any technological advances that show promise of reducing the cost of extracting uranium from seawater.