must / have / should be waiting

[Ofriendragon]

Jack. I ______ go now; the Smiths ______ for me.

A. must; will wait
B must; will be waiting
C. have to ; must wait
D. have to ; should be waiting

I feel B is the best; D is also correct, the speaker should say goodbye earlier, though. Am I right? Please help.

Thanks in advance.

[Lost_Soul]

I'd choose D, because B says that the Smiths will be waiting - I know they are not waiting right now, so why should I bother to leave that suddenly?

[Ofriendragon]

Thank you, soul.
but will can also be a modal verb, meaning it's likely that...
I feel really confused.