Q22:

Unlike mainstream American businesses, more than half of which fail, the failure rate for businesses in the Amish community hovers around 5 percent.

1. Unlike mainstream American businesses, more than half of which fail
2. Unlike mainstream American businesses, in which the failure rate is more than half
3. Unlike mainstream American businesses, where more than half of them fail
4. While the rate of mainstream American businesses failing is more than half
5. While more than half of mainstream American businesses fail                                                                     

   这道题答案是E。一开始可以用逻辑关系排除ABC，但是D的主语是the rate，不是更对应后面的the failure rate吗?

   怎么反而错了呢? 请各位大侠帮我指点一下。