What must be in place if a vehicle equipped with chocks is left unattended?

Answer: B — Chocks must be in place

If a vehicle equipped with chocks is left unattended, it is essential that the chocks are in place to prevent the vehicle from rolling. Chocks act as sturdy blocks that secure the vehicle in a stationary position, especially on an incline or uneven surface. This practice is crucial not only for the safety of the vehicle but also for the safety of personnel and equipment nearby. By using chocks, the risk of accidents caused by unexpected movement of the vehicle is significantly minimized. While it may also be important to turn off the engine, lock the doors, and activate hazard lights for other safety purposes, the specific requirement for a vehicle with chocks focuses on ensuring that the chocks themselves are applied to maintain stability when the vehicle is unattended.