There are only these two possibilities A and B. It was proved that it is not A. So it ... be B.
In the above sorts of sentences, what should be used for the blank: "must", "should" or "have to"?
I found out in my research that "must" and "have to" is for more strong and inevitable obligations such as rules. So, it must be either "must" or "have to"! But I anyway like to know your views about the word choice in my sentence.