BOTH INTERNATIONAL & INLAND You are underway in a narrow channel and are being overtaken by a vessel astern. The overtaking vessel sounds a signal indicating her intention to pass you on your starboard side. If such an action appears dangerous, which signal are you required to sound?

Correct Answer: Option A — Five short and rapid blasts

Rule 34(d) applies when a vessel is in doubt regarding the actions of another. If an overtaking vessel proposes a maneuver that appears dangerous, the overtaken vessel must signal this doubt immediately by sounding at least five short and rapid blasts on the whistle, alerting the other vessel to the hazard.