The state of Montana, in response to "outsiders" controlling ranch properties, has passed a statute that requires $6$ months of residency before an individual can purchase $40$ or more acres of land. The statute is:

The state of Montana, in response to "outsiders" controlling ranch properties, has passed a statute that requires $6$ months of residency before an individual can purchase $40$ or more acres of land. The statute is:

an unconstitutional burden on interstate commerce.

constitutional because all buyers must be residents.

constitutional because the statute applies only to intrastate lands.

a legitimate exercise of state powers.