GWD-30-Q38

题目:

The ancient Nubians inhabited an area in which typhus occurred, yet surprisingly few of their skeletons show the usual evidence of this disease.  The skeletons do show deposits of tetracycline, an antibiotic produced by a bacterium common in Nubian soil.  This bacterium can flourish on the dried grain used for making two staples of the Nubian diet, beer and bread.  Thus, tetracycline in their food probably explains the low incidence of typhus among ancient Nubians.

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

答案是A.        The tetracycline deposits did not form after the bodies were buried.排除他因

但是我觉得B也可以啊,

B: The diseases other than typhus to which the ancient Nubians were exposed would not be affected by tetracycline.

请解答

题意：Nubian人居住在一个Typhus病多发的地方，但他们的尸骨却显示Nubian人很少的这种病。之后又说在他们的尸骨上发现有Tetra...这种抗生素，这种抗生素在Nubian的土壤中很多。（这里我想有一个潜在的意思，就是说这种抗生素可以阻止Typhus这种病发生）。那么用这种土壤上种出来的grain酿出来的啤酒，做出来的面包也就会有很多的这种抗生素。作者认为这就是为什么Nubian人很少得Typhus.

答案一下就出来了。
如果对A取非，说抗生素是人死后形成的，那作者的结论肯定就不成立了。所以A是答案。

关于答案B,对它取非，也就是说，抗生素不单单影响Typhus这种disease，还影响其它的disease.这又何妨呢？只要是它可以影响Typhus就够了。选项取非对作者的结论没有任何消弱，所以错。

clear, thanks a lot

DING