What is the "three-second rule" in driving?

The "three-second rule" in driving refers to a guideline that encourages drivers to maintain a following distance of at least three seconds behind the vehicle in front of them. This measure is crucial for safety, as it provides adequate time to react to sudden stops or changes in traffic.

By maintaining this distance, drivers can better anticipate potential hazards and avoid collisions, especially in situations where traffic conditions can change rapidly. This rule helps to ensure that there is enough space to stop safely if the vehicle ahead suddenly brakes or encounters an obstacle.

In contrast, the other options do not accurately reflect the purpose of the "three-second rule." For example, the notion of changing lanes safely relies on different considerations such as checking blind spots and using turn signals. Speed limits in school zones are critical for ensuring the safety of children but are unrelated to the concept of following distance. Lastly, parallel parking techniques focus on maneuvering the vehicle into a parking space without reference to following distance at all. Thus, the "three-second rule" succinctly encapsulates the importance of maintaining a safe following distance while driving.