— Do you know ?— Next Sunday.A. what they will doB. where they will doC. when they will co

问题补充：

— Do you know ?

— Next Sunday.

A. what they will do

B. where they will do

C. when they will come here

D. who they will meet

答案：

A. what they will do

B. where they will do

(答案→)C. when they will come here

D. who they will meet

解析： 四个选项分别表示要做什么、要做哪儿（语义不通）、什么时候来这和他们要见谁。根据答语下个星期日，可知前文问的是时间，选C。