扫描二维码，直接登录
题库 / Prep2007E1-CR-3
The prairie vole, a small North American grassland rodent, breeds year-round, and a group of voles living together consists primarily of an extended family, often including two or more litters. Voles commonly live in large groups from late autumn through winter; from spring through early autumn, however, most voles live in far smaller groups. The seasonal variation in group size can probably be explained by a seasonal variation in mortality among young voles.
Which of the following, if true, provides the strongest support for the explanation offered?
It is in the spring and early summer that prairie vole communities generally contain the highest proportion of young voles.
Prairie vole populations vary dramatically in size from year to year.
The prairie vole subsists primarily on broad-leaved plants that are abundant only in spring.
Winters in the prairie voles' habitat are often harsh, with temperatures that drop well below freezing.
Snakes, a major predator of young prairie voles, are active only from spring through early autumn.
D和E都是在说两个时间段的区别，为什么D不对呢？因为冬季气温太低，幼崽容易冻死，所以voles聚在一起生活，感觉可以解释问题啊。是因为D选项里没有提到young prairie voles这个关键词吗？求解答，谢谢老师~
D选项说反了嘛～如果说冬天冷，不容易存活的话，那应该是冬天V更少。而原文讲，冬天是large group，春秋才是small group。
我和这个po主理解的一样。。拐了两个弯，我想的是冬天冷所以要聚在一起取暖所以数量多，过度脑补.......
hahaha我也是
explaination就是a seasonal variation in mortality among young voles. 所以答案一定是和死亡率相关的 和取暖没关系 过度脑补。。。
登录 或 注册 后可以参加讨论