How is reaction time defined in driving?

Reaction time in driving is defined as the time taken to recognize a hazard. This involves the cognitive processes of perceiving a potential danger and then deciding to act, whether that means applying the brakes, steering away, or executing another evasive maneuver. It is a critical component of safe driving because recognizing a hazard quickly allows the driver to take the necessary actions to avoid a collision.

The other options represent different aspects of driving but do not accurately define reaction time. The time taken to apply the brakes pertains to the physical response after recognizing a hazard, while the total stopping time includes both recognition and response time and the actual time it takes for the vehicle to come to a stop. Similarly, the time taken to accelerate does not relate to hazard recognition at all, as it refers to the vehicle's speed increase rather than the decision-making process in response to a threat on the road.