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 is vessel "B" in this situation?

Correct Answer: Option D — None of the above

Under COLREGS Rule 34(a), maneuvering signals are only authorized when vessels are in sight of one another and are actively altering course. Simply crossing paths does not mandate signals. Since no alteration of course is occurring, the signal is unauthorized, making the vessel's status irrelevant to the signal's validity.