prep 2上一道语法，找不到讨论，实在不明白，求教大家

In the mid-1920s the Hawthorne Works of the Western Electric Company was the scene of an intensive series of experiments that would investigate changes in working conditions as to their effects on workers’ performance.

A.      that would investigate changes in working conditions as to their effects on workers’ performance

B.       investigating the effects that changes in working conditions would have on workers’ performance

C.      for investigating what the effects on workers’ performance are that changes in working conditions would cause

D.      that investigated changes in working conditions’ effects on workers’ performance

如果我没记错，that只能就近指代，如果你选A，那么That指代的就是Experiments，但是从句子的意思来看并不是的，而是应该指代Scene，所以A，D都可以排除了。

不知道这样讲对不，如果有错希望指正。

无论是that从句还是分词结构都应该是就近修饰experiments，

would have在这里应该是过去将来时，表示changes 将会产生的效果。因此恢复到正常语序应该是changes would have effects on working condition.

因此这里的a选项中的as to 结构就显得很奇怪。不如b选项的结构清晰。

个人意见~

哦，分词就近修饰..

谢谢，又补上个语法漏洞