__________is known to the world,Mark Twain is a great American w

__________is known to the world,Mark Twain is a great American writer.
A、

That


B、

Which


C、

As


D、

It


【正确答案】:C
【名师解析】:这个句子中,"As"引导的是非限制性定语从句,用来补充说明整个主句的内容。在这个定语从句中,"As"相当于"which"或"that",指代整个主句,即"Mark Twain is a great American writer"。因此,选项C "As"是正确答案。其他选项中,"That"和"It"不能引导非限制性定语从句,而"Which"虽然可以引导非限制性定语从句,但在这个句子中并不合适。