What is the "2-second rule" used for in driving?

Answer: B — To maintain a safe following distance

The "2-second rule" is a method used to ensure that drivers maintain a safe following distance behind the vehicle in front of them. By counting two seconds from the moment the vehicle in front passes a fixed point, a driver can gauge whether they are following at a safe distance. This technique allows for adequate reaction time in the event that the car in front suddenly brakes or slows down, which is crucial for avoiding rear-end collisions. When properly applied, the 2-second rule accounts for varying speeds and road conditions. If a driver is able to maintain at least a 2-second gap, it typically indicates that they are maintaining a safe distance. In adverse weather conditions or when driving a larger vehicle that may require more stopping time, increasing this following distance is recommended. Other options provided do not relate to the purpose of the 2-second rule. Signaling a lane change is a different aspect of safe driving practices, while measuring the distance between parked cars and determining safe speed limits involve different rules and calculations that do not pertain to the primary concept of following distance during active driving.