I -----your father------come here next week.

I _____your father______come here next week.
A.suppose;can't
B.don't suppose;can
C.don't suppose;can't
D.suppose;should have
答案上给的是B,但是我很疑问为什么不选C,同样也能翻译只是多了一个not?
知道为什么的请速速回答 Tankes!