BOTH INTERNATIONAL & INLAND Which vessel(s) shall a power-driven vessel underway "keep out of the way of"?

Correct Answer: Option D — All of the above

Rule 18(a) explicitly lists vessels that a power-driven vessel underway must keep out of the way of, including vessels not under command, restricted in their ability to maneuver, engaged in fishing, and sailing vessels. All these categories possess higher priority than a standard power-driven vessel.