—Whichinventiondoyoulikebest?—QQ.Itisaninvention

問題詳情：

 —Which invention do you like best?

—QQ. It is an invention ____________ can help us communicate with others online freely.

A. what             B. that            C. who

【回答】

B

知識點：定語從句

題型：選擇題