Which one of the following is true about can buoys?

Can buoys, specifically identified by their distinctive shape and characteristics, are typically cylindrical and serve particular roles in navigation. These buoys are part of a system used to mark channels and indicate the sides of navigable waterways.

The cylindrical shape of can buoys is useful in distinguishing them from other types of buoys, such as nun buoys, which are conical. This shape aids mariners in recognizing their location when navigating through waters, especially when visibility might be reduced.

While the color of can buoys is indeed a factor in navigation, they are specifically green, contrasting with red nun buoys. Additionally, the indication of hazards is typically not a primary function of can buoys; rather, they can be used to designate a safe channel. The flat top mentioned in the other option is also characteristic of specific types of buoys, such as nun buoys, further differentiating them from can buoys. Thus, the identification of can buoys as cylindrical in shape is essential for the safe navigation in waterways.