Which statement is true concerning lights and shapes for towing vessels?

The statement about the towing vessel needing to carry forward and after masthead lights if it is over 50 meters in length is accurate due to international maritime navigation rules. Specifically, under the COLREGs (International Regulations for Preventing Collisions at Sea), towing vessels that are over 50 meters must display a specific set of lights to ensure visibility and safety while navigating, especially at night or in reduced visibility.

Towing vessels over this length must exhibit both a forward and an after masthead light. The forward masthead light indicates the direction of travel and enhances visibility to other vessels, while the after masthead light serves a similar purpose for the stern of the vessel. This requirement helps other mariners understand that they are observing a towing operation, allowing them to take necessary precautions.

The other statements are inconsistent with the established rules: all towing vessels do not display the same lights regardless of size; different requirements apply depending on their length and the nature of the towing operation. Only the towed vessel displaying lights at night would pose significant safety issues since both vessels must be visible to avoid collisions. Lastly, the towing vessel's emergency lights are not restricted to inclement weather; they must be used when necessary to indicate distress or urgency.