题目

阅读下面短文，从每题所给的A、B、C和D四个选项中选出可以填入空白处的最佳选项。Modern inventions have speededup people's lives amazingly. Motor cars1 a hundred miles in more than an hour, aircraftcross the world within a day, 2 computers operate at lightning speed. Indeed, thislove of 3 seems never-ending. Every year motor cars are producedwhich go even faster and each new computer boasts (吹嘘) of 4 precious seconds in handling tasks. All this saves time, but5 acost. When we lose or gain half a day in speeding across the world in an airplane,our bodies tell 图 8 所示的四个光路图中，MM′为平面镜，PO 为入射光线，ON 为法线，入射角∠PON 等于 60°，其中符合光的反射定律的光路图是A. A B. B C. C D. D