BOTH INTERNATIONAL & INLAND You are underway and hear a vessel continuously sounding her fog whistle. What is this vessel indicating?

Correct Answer: Option B — The vessel is in distress

Annex IV, paragraph 1(b) identifies a continuous sounding with any fog-signaling apparatus as a recognized distress signal. This signal is intended to alert nearby vessels that the vessel is in grave and imminent danger and requires immediate assistance, overriding standard fog signal requirements.