INTERNATIONAL ONLY You are in charge of a 250 meter freight vessel constrained by her draft proceeding down a narrow channel. There is a vessel engaged in fishing on your starboard bow half a mile away. According to Rule 9, which statement is TRUE?

Correct Answer: Option B — If you are in doubt as to the fishing vessel's intentions you may sound at least five short and rapid blasts on the whistle.

Rule 9(d) states that a vessel shall not impede the passage of a vessel which can safely navigate only within a narrow channel. Rule 34(d) allows a vessel in doubt of another's intentions to sound at least five short and rapid blasts to signal that doubt.