请教一道逻辑题

Archaeologists seeking the location of a legendary siege and destruction of a city are excavating in several possible places, including a middle and a lower layer of a large mound. The bottem of the middle layer contains some pieces of pottery of type 3, known to be from a later period than the time of the destruvtion of the city, but the lower layer does not.

The force of the evidence cited above is most seriously weakened if which of the following is true?

A. Gerbils, small animals long native to the area, dig large burrows into which objects can fall when the burrows collapse.
B. Pottery of types 1 and 2, found in the lower level, was used in the cities from which, according to the legend, the besieging forces came.
C. Several pieces of stone from a lower-layer wall have been found incorporated into the remaims of a building in the middle layer.
D. Both the middle middle and the lower layer show evidence of large-scale destruction of habitations by fire.
E. Bronze axheads of a type used at the time of the siege were found in the lower level of excavation.

题目本身看得就不太明白，理解不了，有没有高手指点一下？

谢谢啦！

这是大全-1-20,你搜一下.

我的理解:该题只给了论据,没给出结论.问的是"哪个能削弱论据". 所以找一个"最能证明论据无价值的选项"即可,而不是找一个"能利用论据得出某种结论(不论对错)的选项".

顺便问一下,这套题的第16题你是怎么做的?

16.   In a political system with only two major parties, the entrance of a third-party candidate into an election race damages the chances of only one of the two major candidates. The third-party candidate always attracts some of the voters who might otherwise have voted for one of the two major candidates, but not voters who support the other candidate. Since a third-party candidacy affects the two major candidates unequally, for reasons neither of them has any control over, the practice is unfair and should not be allowed.

If the factual information in the passage above is true, which of the following can be most reliably inferred from it?

(A) If the political platform of the third party is a compromise position between that of the two major parties, the third party will draw its voters equally from the two major parties.

(B) If, before the emergence of a third party, voters were divided equally between the two major parties, neither of the major parties is likely to capture much more than one-half of the vote.

(C) A third-party candidate will not capture the votes of new voters who have never voted for candidates of either of the two major parties.

(D) The political stance of a third party will be more radical than that of either of the two major parties.（B）

(E) The founders of a third party are likely to be a coalition consisting of former leaders of the two major parties.