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___________ Which of the following most logically completes the argument? 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 错选了C，答案给的A。A说女士比男士更可能做志愿活动，女士比男士活得长。这不是支持原文了么？可以题目不是应该驳斥吗？

请问这道题为什么选A不选E呀

K+7= 3n+9 (3n+9 可以除以3, 为什么说 K(K+7) 可以被3整除?) 问题从条件2可以推出n可以被6整除？ 问题3n+9 如何被2整除？搞不明白，老师

这题D和E为什么应该选E呀

请问这道题A选项和D选项的区别是什么，为什么不能选A呀？

这道题为什么选B？E选项的定位句在哪里？

这道题应该怎么判断选E啊，错选了A

这道题选E是因为intact可以做副词吗，D选项为什么不能选

我是看阶段一网课 里面有开根号 就是rate 速率不变，B和速率成反比， A平方和速率成正比，B 增加了100% (2倍), 为了保持速率不变，A平方* 2 为何要开根号？

这道题答案说选D，为什么选D呀

这道题应该怎么判断哪个是main conclusion，哪个是intermediate conclusion