INTERNATIONAL ONLY You are underway in a narrow channel, and you are being overtaken by a vessel astern. After the overtaking vessel sounds the proper signal indicating his intention to pass your vessel on your starboard side, you signal your agreement by sounding which signal?

Correct Answer: Option D — One prolonged, one short, one prolonged, and one short blast

COLREG Rule 9(e)(ii) mandates that the vessel being overtaken in a narrow channel must signal its agreement to the overtaking vessel's proposal. The required signal for agreement is one prolonged, one short, one prolonged, and one short blast, confirming the maneuver can be performed safely.