INTERNATIONAL ONLY In a narrow channel, an overtaking vessel intends to PASS on the other vessel's port side. This overtaking action can only take place if the vessel to be overtaken takes action to permit safe passing. Which signal would the overtaking vessel sound?

Correct Answer: Option C — Two prolonged followed by two short blasts

COLREG Rule 9(e)(i) requires an overtaking vessel in a narrow channel to signal its intent. When passing on the port side, the overtaking vessel sounds two prolonged blasts followed by two short blasts. This signal initiates the coordination required for the overtaken vessel to permit safe passage.