You are towing a large barge on a hawser. Your main engine suddenly fails. What is the greatest danger?

Correct Answer: Option D — The tow will overrun tug.

When main engine power is lost while towing astern, the heavy barge retains forward momentum and inertia. Without the tug pulling ahead, the barge rapidly closes the distance and overruns the tug, posing an immediate collision and crushing hazard to the towing vessel.