Question 711 Rules of the Road

The correct answer is A. According to the International and Inland Navigation Rules, vessels at anchor must display a single all-round white light, which corresponds to shape A in the illustration. This light is required to be visible all around the horizon for a distance of at least 2 miles. The other shapes in the illustration (B, C, and D) are not the appropriate signals for a vessel at anchor. Shape B represents a vessel underway, shape C represents a vessel restricted in its ability to maneuver, and shape D represents a vessel constrained by its draft.