求解一道语法题

serendipityln

So dogged were Frances Perkins’ investigations of the garment industry, and her lobbying for wage and hour reform was persistent, Alfred E. Smith and Franklin D. Roosevelt recruited Perkins to work within the government, rather than as a social worker.

A.    and her lobbying for wage and hour reform was persistent,
B.    and lobbying for wage and hour reform was persistent, so that
C.    her lobbying for wage and hour reform persistent, that
D.    lobbying for wage and hour reform was so persistent,
E.    so persistent her lobbying for wage and hour reform, that
我选的C   答案是E    为什么啊？

njit2007

So.......That置于句首用倒装
and前后平行对称

serendipityln

那 请问 划线部分是独立主格结构吗？