What is the shape of Can buoys in lateral marking?

The correct choice for the shape of can buoys in lateral marking is a green square. These buoys are part of a system used to indicate safe navigation channels in waterways.

In the lateral system of buoy markings, can buoys are used on the port side of the waterway as approaching from the open sea, which helps boaters recognize which side to navigate. The green square shape of the can buoy signifies that it denotes a safe passage on the left side of the vessel. This specific shape and color help in easily distinguishing it from other navigational aids, such as nun buoys, which are shaped like conical points and are colored red.

This distinction is vital for avoiding confusion while navigating, as it provides critical information to sailors regarding the boundaries of navigable waters.