Where are the components of the air brake system primarily located?

Answer: B — Under the vehicle chassis

The components of the air brake system are primarily located under the vehicle chassis, which allows for effective installation and maintenance. This placement ensures that essential parts, such as the air compressor, brake valves, and air reservoirs, are protected from damage that could occur in more exposed areas while also being easily accessible for service and inspection. Having the air brake components under the chassis facilitates a more efficient design for the overall vehicle layout and helps minimize the impact of weight distribution on the vehicle's center of gravity. Properly positioning these components also helps to limit the noise and vibration that could affect passenger comfort within the cabin.