What is the primary function of anti-lock braking systems (ABS)?

Answer: B — To prevent wheels from locking during abrupt braking

The primary function of anti-lock braking systems (ABS) is to prevent the wheels from locking during abrupt braking. When a driver applies the brakes hard, especially on slippery surfaces, the wheels may stop rotating completely, leading to a loss of steering control and increased stopping distances. ABS uses a system of sensors and a computer to monitor wheel speed and can modulate brake pressure to individual wheels, ensuring that they continue to rotate even during heavy braking. This rotational control allows the driver to maintain steering capability and helps to stabilize the vehicle, which is critical for safe maneuvering in emergency situations. While features like improved fuel efficiency, shorter stopping distances, and enhanced engine power are important for vehicle performance, they are not the primary functions associated with the operation of ABS. Instead, the focus on maintaining wheel rotation under heavy braking directly contributes to vehicle safety by improving control during emergency stops.