A preferred-channel buoy may be represented by which characteristic?

A preferred-channel buoy is specifically designed to indicate the side of the channel that is preferred for navigation. These buoys are often characterized by distinct markings and light characteristics that help mariners determine their preferred route.

The correct answer is that a preferred-channel buoy may be represented by a lettered characteristic. This is important because lettered buoys serve as identifiable markers that provide information about the navigation channel. They can be used in conjunction with other buoy types to indicate the preferred direction of travel through a waterway.

While options such as spherical shape or a white light might apply to some buoy types, they do not specifically indicate the preference for a channel. Spherical buoys are generally utilized for mooring and do not provide the same navigational guidance as lettered buoys. Similarly, while a white light can be a characteristic of buoys, it does not universally apply to preferred-channel indicators.

Overall, lettered buoys provide essential information for navigation in preferred channels and are a fundamental part of the navigational system.