INTERNATIONAL ONLY A signal of one prolonged, one short, one prolonged, and one short blast, in that order is given by which vessel?

Correct Answer: Option A — A vessel being overtaken in a narrow channel

Rule 34(c)(ii) requires a vessel being overtaken in a narrow channel to sound a signal of one prolonged, one short, one prolonged, and one short blast to indicate agreement to be overtaken. This signal alerts the overtaking vessel that the maneuver is safe to proceed in the restricted waterway.