GWD18-Q30~求助NN~

wojiaodubing

The ancient Nubians inhabited an area in which typhus occurs, 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?

A.Infectious diseases other than typhus to which the ancient Nubians were exposed are unaffected by tetracycline.
B.Tetracycline is not rendered ineffective as an antibiotic by exposure to the processes involved in making bread and beer.
C.Typhus cannot be transmitted by ingesting bread or beer contaminated with the infectious agents of this disease.
D.Bread and beer were the only items in the diet of the ancient Nubians which could have contained tetracycline.
E.Typhus is generally fatal.

答案是B。Why is C an incorret answer？
谢谢各位NN啦~

ShirleyWong

看来句子理解才是王道啊...

wojiaodubing

我明白了，conclusion的重点是这个抗生素，和病毒没有关系。
Many thanks！

saracarter

抗生素（在dried grain上）--->food ------->low rate of disease. 所以关键的就是抗生素是否还是有效的当它从grain变成food。依赖于加工的过程是否破坏了抗生素的效用。