In emergency braking with air brakes (no ABS), the best method is to:
a.Brake as hard as possible and hold the pedal down
b.Apply brakes firmly without locking the wheels and steer to safety
c.Pump the brakes rapidly
d.Apply the parking brake immediately
Explanation
During emergency braking without ABS, you should apply the brakes firmly while avoiding wheel lockup. Locked wheels cause skidding and loss of steering control. Controlled braking (braking as hard as you can without locking wheels) is the most effective method.