这道逻辑题答案不对吧

31. GWD26-Q31

Which of the following most logically completes the argument?

When people engage in activities that help others,
        their brain releases endorphins, the brain’s natural opiates, which induce in people a feeling of well-being. It has been suggested that regular release of endorphins increases people’s longevity. And a statistic on adults who regularly engage in volunteer work helping others shows that they live longer, on average, than adults who do not volunteer. However, that statistic would be what we would expect even if volunteering does not boost longevity, because    .

A.      in the communities studied, women were much more likely to do regular volunteer work than men were, and women tend to live longer than men do.

B.       the number of young adults who do regular volunteer work is on the increase

C.      the feelings of well-being induced by endorphins can, at least for a time, mask the symptoms of various conditions and diseases, provided the symptoms are mild.

D.      it is rare for a person to keep up a regular schedule of volunteer work throughout his or her life.

E.       Some people find that keeping a commitment to do regular volunteer work becomes a source of stress in their lives.

这道题答案是A，怎么都不明白。C或者E不是更好些吗？哪个最合适呢？

我对划线前最后一句话的意思理解是 “统计结果表明做善事的人长寿”这个事实可能是由于其他明显的原因造成的，A说明了真正的原因是女性比男性长寿。

这个样子啊，嗯，没错，谢了。