奉献So dogged那题 老外解答

Q1:

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.

1. and her lobbying for wage and hour reform was persistent,
   
2. and lobbying for wage and hour reform was persistent, so that
   
3. her lobbying for wage and hour reform persistent, that
   
4. lobbying for wage and hour reform was so persistent,
   
5. so persistent her lobbying for wage and hour reform, that

这是一位外国老师的答案  颇有道理的  我问他 why E NOT C? ^_^   

Benny - 祝你好运, 小饺子! 说:
Tricky again... These guys are getting better and better.
Benny - 祝你好运, 小饺子! 说:
A cannot be used because it would require a reduced gerundial phrase, such as her lobbying, etc., being persistent.
Benny - 祝你好运, 小饺子! 说:
Lobbying here is a gerund but it is a noun.

这道题目还是没有看懂你的解释啊．．．我觉得答案还是Ｃ