(单选题)

According to the author, recent work on snow-blindness shows that it is caused by ______.

A.exposure to bright light

B.failure to focus on an object

C.a loss of vision which doesn’t last long

D.focusing on dark colored objects for a very long time

参考答案：B

参考解析：

细节理解题。根据文章第二段第二句“Rather, a man’s eyes frequently find nothing to focus on in a broad expanse of barren snow-covered terrain”可知，雪盲的产生是因为在一个广阔的贫瘠的白雪覆盖的地形上没有什么可以聚焦，即找不到目标。故选B。

知识点：阅读理解四选一英语专业基础知识阅读理解教师招聘-小学英语