INTERNATIONAL ONLY Two power-driven vessels are crossing within one half mile of each other as shown in illustration D042RR below. Vessel "A" sounds one short blast of the whistle. What does this signal mean?

Correct Answer: Option D — None of the above

Rule 34(a) defines one short blast as an indication that a vessel is altering her course to starboard. In a crossing situation, this signal is not a request for permission or an agreement, but a statement of the vessel's own maneuver. Therefore, none of the provided options accurately describe the signal.