GWD上面原题，求解

梦寻蝶绮

Frobisher, a sixteenth-century English explorer, had soil samples from Canada's Kodlunarn Island examined for gold content.  Because high gold content was reported, Elizabeth I funded two mining expeditions.  Neither expedition found any gold there.  Modern analysis of the island's soil indicates a very low gold content.  Thus the methods used to determine the gold content of Frobisher's samples must have been inaccurate.

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

	The gold content of the soil on Kodlunarn Island is much lower today than it was in the sixteenth century.
	The two mining expeditions funded by Elizabeth I did not mine the same part of Kodlunarn Island.
	The methods used to assess gold content of the soil samples provided by Frobisher were different from those generally used in the sixteenth century.
	Frobisher did not have soil samples from any other Canadian island examined for gold content.
	Gold was not added to the soil samples collected by Frobisher before the samples were examined.

我选的B答案是E,求大神指教。我认为正因为两队不在一处挖掘才能提供证明这个岛的金子不多，才可以说明F的不对。我认为E不能 close 这个gap（为什么两队回来检查说没有金子就说明F错）

梦寻蝶绮

新来的不太懂发帖，前面误加了（逻辑小分队），抱歉

alzn2765

F说的是有，两个探险队出去毛也没找到，说明岛上确实没有。那还有什么可能可以在F的检测黄金方法没有问题的前提下能产生这种结果呢？就是F用自己掺了黄金的C岛上的土去骗伊丽莎白一世呗。

B中两个探险队没有勘探C岛的相同地区，那么只要F检测黄金方法没有问题同时F也没作假，那么两个探险队应该至少有一支发现黄金。

这题的结论不是F说的对不对，而是F用来检测土样中黄金成分的方法有没有错误。

梦寻蝶绮

alzn2765 发表于 2015-8-19 22:40
F说的是有，两个探险队出去毛也没找到，说明岛上确实没有。那还有什么可能可以在F的检测黄金方法没有问题的 ...

噢，好像有点感觉了。抓住method incorrect,正因为没有在检查之前加入金子才能证明之前F的方法不正确，排除了他因。而B这样想的话就是无关选项啦。谢谢！