What is the minimum following distance on a highway under good conditions?

Answer: B — Two seconds

The minimum following distance on a highway under good conditions is two seconds. This guideline is based on the need to maintain a safe space between vehicles that allows for adequate response time to sudden changes in traffic, such as abrupt stops or emergencies. By calculating a three-second gap, drivers can react appropriately without the risk of rear-end collisions. This distance is especially crucial at higher speeds typical on highways, where the increased momentum means that stopping distances are significantly longer than at lower speeds. Furthermore, this two-second rule accounts for typical driving conditions, allowing drivers to adjust their distance based on specific circumstances, such as inclement weather or heavy traffic, which might require a greater following distance for safety.