问题
选择题
．What sets human beings apart from animals is not the pursuit of happiness, but the pursuit of meaning, ________ is unique to humans.
A．that
B．what
C．which
D．as
答案
答案：C
C 考察定语从句。本句是一个非限制性定语从句，which指代整个一句话的内容。As虽然也可以引导非限制性定语从句，但一般是指正如，且常用与被动语态中。故C正确。