这道题答案好像有问题

Q17:

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

1. Concerns about public
        health led to the construction between 1876 and 1904 of three separate
        sewer systems to serve
2. Concerns about public health
        have led to the construction of three separate sewer systems between 1876
        and 1904 to serve
3. Concerns
        about public health have led between 1876 and 1904 to the construction of
        three separate sewer systems for serving
4. There were
        concerns about public health leading to the construction between 1876 and
        1904 of three separate sewer systems servin
5. There were concerns
   leading between 1876 and 1904 to the construction of three separate sewer
   systems for serving