INTERNATIONAL ONLY Two power-driven vessels are meeting in the situation as shown in illustration D037RR below. What does one short blast from either vessel mean?

Correct Answer: Option C — "I am altering my course to starboard."

Rule 34(a) defines one short blast as an indication that a vessel is altering her course to starboard. When two power-driven vessels are meeting head-on, this signal informs the other vessel of the maneuver being executed to comply with the requirement to pass port-to-port under Rule 14.