What does the air brake system in commercial vehicles primarily prevent?

Answer: B — Brake failure due to overheating

The air brake system in commercial vehicles is primarily designed to prevent brake failure due to overheating. In heavy-duty applications, such as with large trucks and buses, the air brake system utilizes compressed air to activate the brakes. This system is essential for managing the substantial heat generated during braking, especially during long descents or continuous braking situations. When traditional brake systems overheat, they can become less effective, leading to what is known as brake fade. However, air brakes are engineered to mitigate this risk by dissipating heat more effectively and maintaining their stopping power under demanding conditions. This is particularly important for vehicles that carry heavy loads and require reliable stopping capabilities to ensure safety on the roads. While other factors such as skidding on wet roads, fluid leaks, and increased stopping distance are important considerations for overall vehicle safety, the air brake system is specifically aimed at preventing overheating-induced brake failure, which is crucial for the safe operation of commercial vehicles.