"닭찜에 간장을 넣어야 합니까?"
Translation:Do I have to add soy sauce to the braised chicken?
1) Do I have to can't be shortened to 'Do I've to,' don't give that as the correct answer!
2) 해야 해 can mean "should" just as much as "must," so I think that should be accepted as well (should I? instead of do I have to)