In illustration D044NG below, what type of buoy is indicated by the letter D?

Correct Answer: Option A — nun

In standard USCG buoyage terminology, a nun buoy is conical in shape. It is designed to be kept on the starboard side of a vessel when proceeding from seaward. Illustration D044NG identifies this specific conical shape, which is distinct from the cylindrical can or pillar buoy types.