What happens if the control line to the trailer disconnects while driving?

If the control line to the trailer disconnects while driving, the correct response is that the driver can still make a controlled stop. This is primarily because most trailers are designed with independent braking systems. When the control line is disconnected, the service brakes of the trailer may not engage, but the driver can still maintain control over the towing vehicle's brakes to slow down and come to a stop safely.

Understanding this is crucial for operating heavy trailers, as it emphasizes the importance of the towing vehicle's braking system in maintaining control and safety even when there are issues with the trailer's connections. While navigating this situation, a driver should remain calm and focus on safely bringing the vehicle to a halt, as immediate stopping may not be necessary or safe depending on the driving conditions.

The other options suggest scenarios that are less likely or not reflective of how braking systems operate when there's a disconnection. The focus should be on utilizing the existing vehicle controls effectively to ensure safety and control while addressing any equipment failure.