问题
选择题
There is hardly an environment on earth ______ some species of animal or other have not adapted successfully.
A．to which
B．in which
C．for which
D．on which
答案
A
题目分析：考查定语从句：先行词是an environment，定语从句中adapt后面缺少介词to，用to which引导定语从句。句意：地球上很难有一种环境，一些动物和其他的物种不能成功的适应的。选A。