What safety feature ensures a vehicle can stop more effectively under heavy loads?

Answer: C — Properly functioning air brakes

The safety feature that ensures a vehicle can stop more effectively under heavy loads is a properly functioning air brake system. In commercial vehicles, such as trucks and buses, air brakes are critical for ensuring that the vehicle can safely and effectively slow down or stop, especially when carrying heavy loads. This system utilizes compressed air to apply pressure to the brakes, allowing for greater control and power compared to other braking systems. When air brakes are properly maintained, they provide the necessary stopping force, accommodating the additional weight and potential momentum of heavy loads. This is particularly important in maintaining safety on steep declines or during emergency situations where quick stopping is essential to prevent accidents. While an anti-lock braking system (ABS) enhances control during braking, especially in slippery conditions, it does not directly address the needs of stopping with heavy loads as effectively as a well-functioning air brake system. Power steering aids in maneuverability but does not impact braking performance. Escape ramps are safety features designed for use in emergencies but do not enhance a vehicle's standard stopping ability under load. Hence, the choice of properly functioning air brakes is key for safety in heavy-load situations.