补全对话
从方框中选出适当的句子，完成对话，有两项为多余选项。

A：Hello,Peter!      
B：Certainly!      
A：Whichofthesedoyouthinkisthemostusefulinvention,acomputer,atelephoneora
television?
B：      
A：Why is that?
B：Oh, I think it can help us work and play.
A：      
B：      , maybe it was invented in 1946.