[求助]gmatprep的一道题

A study on couple's retirement transtions found that women who took new jobs after retiring from their primary careers reported high marital satisfaction, more than when retiring completely.

A.more than when retiring

B.more than if they were to retire

C.more so than those retiring

D.which was more so than those retiring

E.which was more than if they had retired

答案：C

请问，这里的so是不是指代reported high marital satisfaction? more 修饰动词？

women (who... ) more reported marital satisfaction than those (retiring...) （did）

请大家帮忙分析一下这个句子的结构。谢谢！

more women (who took new jobs after retiring) reported high marital satisfactiong than those women retiring compeletely