The following persons are exempt from driver’s licensing requirements:
1. Any person while operating a military motor vehicle in the service of the armed forces of the United States.
2. Any person while operating a farm tractor or implement of husbandry to or from the home farm buildings to any adjacent or nearby farmland for the exclusive purpose of conducting farm operations.
3. A nonresident operating a motor vehicle within the legal scope of the nonresident’s home state or country license except a nonresident may operate a commercial motor vehicle only in compliance with section 321.174.