Here is the interesting thing about “have to” and “must.” When you use them in a positive sense (without a “not”), they both mean the same thing: that something is required. Example: “Tomorrow is Monday, so I have to (must) go to work.” But when they are used with “not,” they do not mean the same thing. “Don’t have to” means “you are not required to do something, but you can do it if you want to.” Example: “I don’t have to work overtime tonight (i.e., my boss is not requiring me to work overtime), but I’m going to because I want the extra money.” In contrast, “must not” means “required not to do something.” Example: “You must not show disrespect to your elders.”

The first one is tricky. It is not (directly) one of your options.

What do you think?