Question 424 Rules of the Road

The correct answer is C) Two white masthead lights in a vertical line. According to the International Regulations for Preventing Collisions at Sea (COLREGS), a vessel that is underway, but not under command, or restricted in its ability to maneuver, must display two white masthead lights in a vertical line in addition to the required sidelights. Since the vessels are passing 1/4 mile apart, this indicates they are not overtaking or crossing, and are simply meeting on the river. Therefore, the vessel "B" would display the two white masthead lights in a vertical line, in addition to the sidelights. The other options are incorrect because a special flashing yellow light is not a required navigation light, towing lights are only displayed by vessels engaged in towing operations, and there is no requirement for two white masthead lights in a horizontal line for a vessel meeting another vessel in this scenario.