The Legislature Passed a Law That Prohibits Vehicles in Any

The legislature passed a law that prohibits vehicles in any state park. The law defines a vehicle as an object with wheels. Last month, Mike was given a ticket while pushing a baby stroller through the park. If Mike challenges his ticket on constitutional grounds, the most effective legal challenge is based on which argument?

A) The law is void for vagueness.
B) The law is an ex post facto law.
C) The law violates the equal protection clause.
D) The law does not satisfy the rational basis test.