Modals 2 - Necessity / Lack of Necessity

Choose the correct modal (helping verb) to complete the sentence.

Bicycle riders --- have tomust notdon't have tomust have a driver's license to ride. It's not necessary.
People who ride motorcycles --- have tomust notdon't have tomust have a driver's license. It is the law.
Drivers on the freeway --- have tomust notdon't have tomust be very careful because speed kills!
People who ride horses --- have tomust notdon't have tomust take their horses on the freeway! That would be a stupid thing to do!