____________ had made great contributions to science is a fact.
A、What he
B、Which he
C、He
D、That he
【正确答案】：D
【题目解析】：句子的意思是“他为科学做出了巨大的贡献（这件事）是个事实”，（翻译的符合中文习惯就是：的确，他为科学做出了巨大的贡献。）That 做主语，后面的he had made great contributions to science 是解释这个that是什么的，是个同位语从句。要用what 的话，后面的句子要么会缺一个主语，要么缺宾语。但he had made great contributions to science是个完整的句子，所以不能用what.
