What distinguishes a "navigable waterway"?

A "navigable waterway" is defined by its ability to accommodate vessels of varying sizes, making this the correct answer. This definition is essential for understanding navigation laws and practices, as it indicates that the waterway supports the safe passage of different types of boats, ranging from small recreational crafts to larger commercial vessels.

The depth of the waterway is important, but it does not specifically define navigation capability; a waterway can be navigable without being a certain depth, as long as it allows for safe transit. While buoys may mark navigable channels for guidance, the presence of markers does not inherently determine a waterway’s navigability. Furthermore, navigable waterways are not restricted solely to commercial vessels; they also serve recreational and other types of vessels, allowing a broad range of usage for various types of craft.