Question

【题目】Scientists think calculating is a necessary skill_________ they base their researches.

A. on it B. on that

C. on which D. on whose

Answer 1

【答案】C

【解析】考查定语从句。句意：科学家认为计算是一种依据他们的研究为基础的必须技能。 base on....意为“依据......为基础”。a necessary skill做先行词，指物，在后面的定语从句中做on的宾语，故选C。