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？

如果n是19的话n+1才是20。那a20不是应该等于a19+19吗，为什么会加20呢？条件二给的公式不是说a(n+1)=a(n)+n吗？我算的是1+2+...+19+19这样

@陆旭老师 第39题要怎么做呢？

@唐小梅老师 这道题用您的方法咋做呀？

@英吉老师 第715题的b选项为啥不算说了原文解释的对立面。是不是因为它主要讲的是electricity不是fossil fuel？ e选项这个地方算是要知道的常识吗？因为当时排除掉e选项就是因为自己脑袋里根本没有这个概念，感觉与原文无关。但是一旦听你说了，接受了说这个设定我是能理解的。所以以后再碰到这种不确定的情况，就默认判定这个选项是可行的，然后再去结合文章看是否支持原文逻辑链吗？

@陆旭老师 当出现overlapping info时，应该用matrix比较好还是用韦恩图比较好？

@英吉老师 如果这道题选了a，算是犯了什么错误？

请问老师这道题是不是答案给错了？不应该是4+8+12+...+200求和吗

想问一下小梅老师这道题的思路

想问一下小梅老师这道题如何快速得出答案？感觉自己解题思路有问题 2分钟内无法解答 类似题有没有什么快速切入的技巧？

A为什么不行？