This is the island ----was bought by a millionaire A it B that C this D/

问题描述:

This is the island ----was bought by a millionaire A it B that C this D/

这是一个that引导的定语从句。

中间是that

B、that 在这里引导定语从句(修饰island),在定语从句中做主语,可以省略。B、D都正确

B that
中间连词

This is the island that was bought by a millionaire.
翻译:这就是一位百万富翁买的那座小岛.
that引导定于从句,并且在句子做主语.
不可能选D,此处缺少句子成分,所以要填上可以做主语的that 或which.