What is the primary function of the air brake system in a commercial vehicle?

Answer: B — To aid in slowing down and stopping the vehicle

The primary function of the air brake system in a commercial vehicle is to aid in slowing down and stopping the vehicle. Air brakes use compressed air to operate brake chambers that push brake shoes against the brake drums, effectively slowing the vehicle's momentum. This system is vital for large commercial vehicles, as they require a greater braking force due to their size and weight. Air brakes allow for quicker and more reliable stopping power compared to other systems, ensuring safety during operation under various conditions. Understanding this function is essential for safe driving practices and compliance with regulations regarding heavy vehicle operation.