How is controlled braking defined?

Answer: B — Squeezing brakes firmly without locking them up

Controlled braking is defined as squeezing the brakes firmly without locking them up. This technique is essential for maintaining vehicle control while slowing down or stopping, especially in large vehicles. By applying the brakes with a steady pressure, the driver can effectively reduce speed without losing traction or causing the wheels to skid. This method allows for better vehicle stability and responsiveness to steering inputs, which is crucial for safe driving in various conditions. The other methods mentioned involve different approaches to braking. Braking hard and quickly can lead to loss of control, particularly on slippery surfaces. Pumping the brakes periodically might be used to avoid wheel lockup in certain situations, but it is not as effective as controlled braking for maintaining overall control when coming to a stop. Lastly, applying brakes only when necessary may not accurately reflect the gradual deceleration required in many driving conditions, potentially leading to unsafe driving practices.