What is the function of the Anti-lock Braking System (ABS) in a commercial heavy vehicle?

1. To shorten stopping distances on dry pavement by 90%
2. To prevent wheel lockup during emergency braking, maintaining directional steering control and preventing tractor jackknifing or trailer swing
3. To allow the vehicle to drive at 120 km/h in dense fog
4. To eliminate the need for routine brake pad maintenance