INTERNATIONAL ONLY You are on vessel "A" as shown in illustration D032RR below. Vessel "B" sounds two short blasts. What action should you take?

Correct Answer: Option C — Do not answer the whistle signal from vessel "B"

Rule 34(a) dictates that whistle signals are only used to indicate maneuvers when vessels are in sight of one another. Because International Rules do not use signals to request or grant permission to pass, there is no requirement to answer a signal from another vessel in a crossing situation.