题目

According to a report by the China News Weekly, Chinese white collars are becoming fully occupied in the office. They pursue many of their activities in the office building, eating, doing exercise, resting, playing games or even dating. In large cities such as Shenzhen, Shanghai and Beijing, where economy is developing at a fast speed, office workers face an increasing work pressure day by day and many of them have begun to make office their home. As the young generation in society, most of them are aged between 25 and 45. In the eyes of outsiders, they enjoy a comfortable life: they lead the 某质点的运动图象如图所示，则质点（ ）A．在第1s末运动方向发生变化B．在第2s末运动方向发生变化C．在第2s内速度越来越大D．在第3s末速度越来越小