What should happen to the brake pedal when a leak is present?

Answer: B — The pedal may sink to the floor

When there is a leak in the braking system, the brake pedal may sink to the floor. This occurs because the loss of air pressure or fluid due to the leak makes it impossible for the brakes to maintain their proper tension. Normally, a well-functioning brake system allows the driver to apply pressure to the pedal, resulting in a firm feeling, which helps in stopping the vehicle effectively. However, if a leak compromises this system, there won't be enough pressure to keep the pedal elevated, making it feel soft or causing it to sink as the driver presses down on it. This phenomenon indicates a serious malfunction and requires immediate attention to ensure the safety of the vehicle and its occupants. Recognizing a sinking brake pedal as a sign of a leak can help prevent potential accidents resulting from brake failure.