Answer :
Final answer:
The tractor protection valve will close and the trailer's emergency brakes will come on when there is a major leak in the brake line.Thus option C) emergency is correct answer.
Explanation:
The tractor protection valve will close and the trailer emergency brakes will come on when there is a major leak in the brake line.
The tractor protection valve is a safety feature in air brake systems of commercial vehicles. It is designed to protect the trailer's braking system in the event of a major leak in the brake line.
When the tractor protection valve closes, it isolates the trailer's brake system from the tractor's air supply. As a result, the trailer's emergency brakes will activate, bringing the vehicle to a controlled stop and preventing further damage or accidents.