Which vessels are considered “power-driven vessels” under COLREGs?

Answer: B — Vessels propelled by machinery

Under the COLREGs, the term "power-driven vessels" specifically refers to vessels that are propelled by machinery. This includes any vessel that utilizes an engine or mechanical means to move through the water, regardless of size or purpose. The classification encompasses a wide range of vessels, such as cargo ships, tankers, and any other types that rely on mechanized propulsion. This definition is crucial because it establishes how these vessels are required to navigate and adhere to specific rules and regulations concerning safe passage and interaction with other types of vessels, like sailing vessels or fishing boats, which may not be power-driven. Other options provided do not meet the criteria defined by COLREGs for power-driven vessels. For example, while fishing vessels can be considered power-driven if they are equipped with engines, they are primarily categorized based on their use, rather than their means of propulsion. Similarly, recreational sailing vessels rely on wind for propulsion and, thus, do not fall under the category of power-driven vessels.