Question

---Are Mr. and Mrs. Black at home?   --- No. ________ of them are at work.

A．Every

B．Each

C．Both

D．All

Answer 1

C

Mr. and Mrs. Black为两个人,both表示两者都。整句理解为：布莱克夫妇在家吗？没有。他们俩都在上班。所以选C。