What's the seat belt rule for drivers under 18 and their passengers?

• Only two people in the car, seat belts or not
• Any number of people, but everyone needs a seat belt
• The number of people can't exceed the number of seat belts, and all must buckle up
  Explanation:

  "For drivers under age 18, the number of vehicle occupants is limited to the number of safety belts originally installed and all occupants must wear safety belts."
• No restrictions on the number of occupants