What is the distinguishing feature of a nun buoy?

A nun buoy is characterized by its conical shape and red color. This design is crucial for navigation as it conveys specific information to mariners about the channel and navigation rules. The conical shape allows for easier identification and ensures that the buoy is easily distinguishable from other types of buoys in the water.

When a mariner sees a nun buoy, they understand that it indicates the right side of a navigational channel when approaching from the seaward side. This feature is part of the IALA (International Association of Lighthouse Authorities) buoyage system, where different shapes and colors signify specific meanings to aid safe navigation. The red color further reinforces its meaning under the navigation rules, as red buoys often represent a safe pass on the starboard (right) side of the vessel.

In contrast, other options describe features that do not align with the recognized characteristics of a nun buoy. For instance, a flat and rectangular shape does not apply here, as this description is more suited to a different type of navigation aid. Bright yellow is typically associated with special purpose markers rather than nun buoys, while round and white describes buoys that signify a different navigational meaning altogether. Therefore, the conical shape and red coloration of a nun buoy serve as