单选题
Some animals that cannot see can still tell the difference between light and darkness, while others can react to chemicals, which is something like smelling and tasting. However, there may be a sense that we know nothing about, for otherwise it is very hard to explain how birds, animals and even insects and fish manage to travel long distances without losing their way.
一些没有视觉的动物，仍能辨别出光线和黑暗的不同，而其它一些动物能对化学物质做出反应，就如同有味觉和嗅觉一样。然而，一定存在一种我们不知道的感觉。因为如果不是这样的话，就很难解释为什么鸟、动物甚至昆虫和鱼能旅行很长的距离而不迷路。
相关内容： 2013年自考英语每日一练汇总
（责任编辑：中大编辑）
