[解析]
(1)C.推理判断题。根据第一段This is the greatest mystery of our adult life:How can we spend all day typing at a computer and go home feeling exhausted?How could merely activating the small muscles of our fingers leave us worn out at the end of the day?What causes mental fatigue?(这是我们成年生活中最大的谜题:为什么我们整天都在电脑前打字,回家后却感觉筋疲力尽?一天下来,仅仅活动一下手指上的小肌肉,怎么会让我们筋疲力尽呢?什么导致精神疲劳?)以及第二段中"It is kind of a mystery,to be honest." said Michael Inzlicht,a University of Toronto psychologist who studies self﹣control,motivation,and fatigue.But scientists do have some clues.There is a hypothesis for why we get so tired from work when we're not physically active. ("说实话,这有点神秘。"多伦多大学研究自我控制、动机和疲劳的心理学家Michael Inzlicht说。但科学家们确实有一些线索。有一种假说可以解释为什么我们在不运动的情况下会因为工作而感到疲惫。)可推知,作者在第一段问了这么多问题是为了引入主题,引起读者注意。故选C。
(2)B.词句猜测题。根据第一段中This is the greatest mystery of our adult life:How can we spend all day typing at a computer and go home feeling exhausted?How could merely activating the small muscles of our fingers leave us worn out at the end of the day? (这是我们成年生活中最大的谜题:为什么我们整天都在电脑前打字,回家后却感觉筋疲力尽?一天下来,仅仅活动一下手指上的小肌肉,怎么会让我们筋疲力尽呢?)可知,这是我们成人生活中最大的谜团:我们怎么能整天在电脑前打字,回家时却感到筋疲力尽?仅仅激活我们手指上的小块肌肉怎么会让我们在一天结束时疲惫不堪呢?是什么导致了精神疲惫?故划线词意思是"疲惫"。A.excitement兴奋;B.tiredness疲惫;C.health健康;D.disability残疾。故选B。
(3)B.细节理解题。根据第二段中We become less motivated to do the task.We become drawn to the things we want to do (browsing social media or reading music blogs,for instance) rather than the things we have to do.And this tension possibly causes fatigue. (我们变得不那么有动力去完成任务。我们被我们想做的事情所吸引(比如浏览社交媒体或阅读音乐博客),而不是我们必须做的事情。这种紧张可能会导致疲劳。)可知,缺乏完成任务的动力会导致疲劳解释了为什么我们在一天的工作后经常感到疲惫。故选B。
(4)D.细节理解题。根据第五段中"If you're typing at work,and if you're anything like me,you got a few browsers open.These lead to temptations,"he said. "Temptations make us less motivated to do our work,which,in turn,may make us tired."(他说:"如果你在工作时打字,如果你像我一样,你会打开几个浏览器。这些导致了诱惑,诱惑使我们工作的积极性降低,这反过来可能使我们疲劳。")可知,Inzlicht会同意D选项"打开一些浏览器打字有时会让我们更累"。故选D。