Which signal sequence indicates a vessel is aground in fog?

• A. Three distinct bell strokes, five seconds of rapid bell ringing, then three distinct bell strokes
• B. Two prolonged blasts
• C. One prolonged blast and two short blasts
• D. One short blast every minute

Answer: (A)

In fog, ships use standardized sound signals to convey their status, and the one that specifically indicates a vessel is aground is a bell pattern. The signal is three distinct bell strokes, followed after a short pause by five seconds of rapid bell ringing, then three more distinct bell strokes. This bell-based sequence is distinctive and clearly communicates that the vessel is grounded, prompting others to keep clear and navigate around the obstruction.

The other signals are not the grounded-vessel indication; they are standard signals used for different maneuvers or statuses under restricted visibility and do not convey the same hazard message as the bell-grounding pattern.