In general, which of the following is least likely to unconstitutionally burden interstate commerce?
1) A state law requiring that all state vehicles burn gasoline produced and refined within the state.
2) A state law imposing tougher purity standards on food imported from out of state than from food produced in-state.
3) A state law requiring in-state liquor distillers to post the prices at which they will sell in-state, and not to exceed those prices when they sell in other states.
4) A state tax on gasoline that makes it more expensive for trucking companies to route their trucks through the state.
Select the correct answer from the choices above.