What are the benefits of HOV lanes?

• It can improve highway infrastructure by moving more people in fewer cars.
• It can reduce the number of vehicles on the road.
• It can encourage carpooling and transit use by providing a more reliable trip time.
• All of the above.
  Explanation:

  "HOV lanes benefit all drivers, not only those who carpool, in the following ways: 1) Improves highway infrastructure by moving more people in fewer cars. 2) Reduces the number of vehicles on the road. 3) Reduces overall emissions and improves air quality."