GWD-12-Q29请教

heavennancy

GWD-12-Q29:

The Earth’s rivers constantly carry dissolved salts into its oceans.  Clearly, therefore, by taking the resulting increase in salt levels in the oceans over the past hundred years and then determining how many centuries of such increases it would have taken the oceans to reach current salt levels from a hypothetical initial salt-free state, the maximum age of the Earth’s oceans can be accurately estimated.



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



A.      The quantities of dissolved salts deposited by rivers in the Earth’s oceans have not been unusually large during the past hundred years.

B.      At any given time, all the Earth’s rivers have about the same salt levels.

C.      There are salts that leach into the Earth’s oceans directly from the ocean floor.

D.      There is no method superior to that based on salt levels for estimating the maximum age of the Earth’s oceans.

E.       None of the salts carried into the Earth’s oceans by rivers are used up by biological activity in the oceans.

我一开始选了E，不选它的原因是因为它太绝对了吗？

dabianfu

如果我做这题，我选A，因为是典型的not+weaken的做法。E不选是主要因为无关，也有点太绝对化了。

我是好宝宝

我觉得题目中说的是resulting increase,就是已经考虑过生物利用的净提高，所以E是一个无关选项