What can you do to prevent brakes from being applied when backing a MEP 12?

Choosing to block surge brakes is the correct approach for preventing brakes from being applied when backing a MEP 12. Surge brakes are designed to apply braking force automatically when the towing vehicle slows down or backs up, which can create issues during the reversing process. By blocking these surge brakes, you effectively disable their automatic function, allowing for smoother and safer backing maneuvers without unexpected braking.

The other options do not address the specific issue with surge brakes effectively. Engaging the emergency brake would actually increase the risk of accidents, as it could lock the vehicle in place. Using a spotter is beneficial for visibility and safety during backing but does not prevent the surge brake system from activating. Reducing speed before backing can help with control but does not prevent the surge brakes from engaging, which is the primary concern.