Complete the sentence using the most appropriate word from below:

I ( ) hurry or I'll be late.

a. must
b. mustn't
c. had to

This is a question from
"Basic Grammar in Use with answers Self-study reference and practice for students of English Second Edition"
(by Raymond Murphy with William R. Smalzer )

According to that book, the answer is c (had to).
Why "HAD(not "have") to" is good here?
MUST sounds much better, I think.
If the option is "have to", it will surely match here, though.
Is this simply a misprint?