OG-3 求助！

The average life expectancy for the United States population as a whole is 73.9 years, but children born in Hawaii will live an average of 77 years, and those born in Louisiana, 71.7 years. If a newlywed couple from Louisiana were to begin their family in Hawaii, therefore, their children would be expected to live longer than would be the case if the family remained in Louisiana.

Which of the following statements, if true, would most significantly strengthen the conclusion drawn in the passage?

B. Environmental factors tending to favor longevity are abundant in Hawaii and less numerous in Louisiana.

C. Twenty-five percent of all Louisianans who move to Hawaii live longer than 77 years.

如果之前没有上过费云杰的课，自然而然就选了B。可是上了他的网络课堂，听了他的解题思路就觉得C是正确的啊！

问题：strengthen 表明文章是加强型演绎题，而且文章是原因结论型文章，因此解加强型题目的思路为1：假设型加强：把前提和结论有差异的概念连在一起构成加强。2：直接加强：仅仅加强结论而不管前提说什么，只举一个例子表明结论是正确的。

很明显C选项就是2直接加强的思路啊！

可是OG的解释为：If B is true, the greater abundance of longevity-promoting environmental factors it mentions is probably at least partly responsible for the higher life expectancy in Hawaii. Children born in Hawaii benefit from these factors from birth, and thus Louisianans who have children in Hawaii increase their children’s chances of living longer. Therefore, B is the best answer. C and E, in the absence of other relevant information, have no bearing on the conclusion; thus, they are inappropriate.

听上去也有点道理！奇怪了！各位NN，求助！谢谢

还是要以OG为准，这题的推理很简单，因为夏威夷的人必路易斯安娜的人活的长，因而在夏威夷的出生的人活得长～～

B是把前提与结论的差异连在了一起，当然是加强～～

而C则跳出了逻辑推理线路，因而是个无关选项～～

而且你体会一下，25％的活到了77岁以上，就一定证明结论正确吗？

To Kevintong: 看了你的解释，觉得是有道理，如果用无关项排除的话，那么B也排除了。谢谢！

To Bigmouse: B选项把前提和结论联系在一起了，也就是架桥梁。我还想问的是：是不是架桥梁中可以有无关词出现（例如这里的Environment factor），还是说架桥梁与无关词没有任何关系？

谢谢！

那不能这么绝对～～～

其实这里的Environment factor是有关的词语，你想想看，这里其实是说两个地方的人寿命不一样，环境当然是一个相关的因素。