INTERNATIONAL ONLY At night you sight the lights shown in illustration D066RR below. What do the lights indicate?

Correct Answer: Option C — A tug with a tow alongside

Rule 24(c) describes the lights for a vessel pushing ahead or towing alongside. A power-driven vessel exhibiting two masthead lights in a vertical line and sidelights indicates a tug engaged in towing. This configuration identifies the vessel's status as a towing unit rather than an independent vessel.