单选题缺宾语从句引导词和宾语从句的主语。四个选项只有A中有that引导宾语从句，后面还有名词短语作从句主语。Experiments related to the sense of smell are more easily _____ than those related toperception of color.无

A、 setting them up
B、 to set up
C、 set up
D、 sets up those

【正确答案】 C

【答案解析】句意：关于味觉的试验比那些关于色觉的试验更容易做。很明显这里谓语动词要用被动语态，只有选项C满足要求。