Which type of suspension system is most commonly found in school buses?

Answer: B — Air suspension system

The most commonly found suspension system in school buses is leaf spring suspension. Leaf springs are renowned for their durability and ability to bear heavy loads, qualities that are essential for school buses which transport multiple students and must maintain safety and stability under various driving conditions. Leaf spring suspension systems consist of multiple layers of metal strips (the leaf springs) that are curved in a way that allows them to flex and absorb shock while maintaining a stable stance. This design effectively distributes the weight of the vehicle and its passengers, reducing body roll and enhancing ride quality. Additionally, the simplicity and cost-effectiveness of leaf spring systems make them an ideal choice for school buses, which often operate under demanding service conditions. While other suspension types, like air suspension and independent suspension, offer certain advantages—such as improved ride comfort and handling—they are less common in school buses mainly due to the higher costs and complexity they introduce. Rigid suspension systems are typically not used in school buses because they do not provide the necessary comfort and flexibility for passenger transport. Therefore, leaf spring suspension remains the preferred choice in this context.