A、  B、  C、  C问题是选择疑问句，对方可以在A和B之间选择一个，或者可以两者都不选，也可以两者都选。问题问听话者是现在通话还是等会再打，(C)回答说“您随意“，意思是他无所谓，因此(C)是正确答案。这种类型的疑问句也

Where do you want me to deliver this package?
(A) At 2 o’clock, if possible.
(B) Right here. Thanks.
(C) By evening, I promise.

Can we speak now or should I call later?
(A) Late last night, at around 11.
(B) No, I’m not late.
(C) Whichever’s best for you.