Why should you turn your front wheels to the right when parking downhill on the right side of a street?

• So the vehicle rolls into traffic if it moves
• So the vehicle rolls off the road and not into traffic if it moves
  Explanation:

  "Turning your wheels to the right ensures that if your vehicle moves, it will roll toward the curb or roadside instead of into traffic, reducing the risk of an accident. If there’s a curb, let your front tire rest against it for extra security."
• To prevent collision with the vehicle behind
• None of the above