A、  B、  C、  C问题是在have上加了not的否定疑问句。去掉not来思考，便可轻松解题。问的是有没有告诉Matthew更改的事项，(C)选项说不用担心，昨天已经说过了，因此是正确答案。

Will our supplies get delivered on time?
(A) A short while ago.
(B) Let’s hope so.
(C) At the warehouse.

Haven’t you told Matthew about the change?
(A) He spoke about it.
(B) Yes, I’ll tell everyone.
(C) Don’t worry, I already told him yesterday.