GMAT Prep上一道语法问题

自由心证

Concerns about public health led to the construction between 1876 and 1904 of three separate sewer systems to serve metropolitan Boston.

A.      Concerns about public health led to the construction between 1876 and 1904 of three separate sewer systems to serve

B.      Concerns about public health have led to the construction of three separate sewer systems between 1876 and 1904 to serve

C.      Concerns about public health had led between 1876 and 1904 to the construction of three separate sewer systems for serving

D.     There were concerns about public health leading to the construction between 1875 and 1904 of three separate sewer systems serving

E.      There were concerns leading between 1876 and 1904 to the construction of three separate systems for serving



答案不是B, 请教nn，那答案应该是哪一个呢？为什么？谢谢。

Sorry. 很明显我啊错地方了。请斑竹删掉本贴，谢谢！