Your vehicle is fitted with anti-lock brakes and something steps into your path. What is the correct way to use them in an emergency stop?

Why D is correct

Anti-lock brakes exist to do something no human foot can manage: modulate each wheel dozens of times a second, holding each tyre just short of the point where it would lock. When a driver pumps, they interfere with a system already performing that task better, and every release surrenders braking force that had been won. The correct input is firm continuous pressure — harder than feels comfortable — held while steering around the hazard. The juddering under your foot and the noise from underneath are the system working, not a fault, so the urge to ease off has to be overruled.

Why the other options are wrong

A. Brake halfway and release repeatedly to keep the wheels turning

Releasing repeatedly is pumping under another name. Each release gives back deceleration already achieved, exactly when there is least distance left to spend it in.

B. Use the parking brake instead, which stops faster on dry roads

A parking brake acts on two wheels and develops nothing like the force of the service brakes. On dry pavement it is strictly worse and mostly good for skid games.

C. Pump the pedal rapidly, since that is how you avoid a skid

Pumping was correct for straight brakes without ABS. On an ABS-equipped car it overrides the very modulation the system is carrying out and lengthens the stop.

On the road

A learner practising emergency stops is startled by the pedal juddering underfoot. Instinct says release; technique says push. Having rehearsed it once in an empty car park is what matters when something steps out, because nobody has ever learned to trust that sensation for the first time in the middle of a real emergency.

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