Besides wildlife on land there are species living in the oceans we still know little.A.

问题补充：

Besides wildlife on land, there are species living in the oceans we still know little.

A. about which

B. in which

C. for which

D. with which

答案：

(答案→)A. about which

B. in which

C. for which

D. with which

解析：句意：除了陆地上的野生动物，海洋中还有一些我们知之甚少的物种。这个句子中包含一个介词+关系代词引导的定语从句，know about是固定用法，意思是知道，了解，选A。