The driver’s reaction distance is the distance covered by the vehicle:

1. From the moment the driver steps on the brake pedal until the vehicle makes a complete stop.
2. Correct answer: From the moment the driver identifies the danger ahead until the moment he begins to react to the danger.
3. From the initial reaction until the end of the vehicle’s braking.
4. From the moment the driver identifies the risk ahead until the vehicle makes a complete stop.

WhyReaction distance runs from the moment the driver notices the danger until they start to act. Braking is not part of it.