INLAND ONLY While underway and in sight of another power-driven vessel forward of your beam, more than 0.5 mile away, you put your engines full speed astern. Which statement concerning whistle signals is TRUE?

Correct Answer: Option A — You need not sound any whistle signals.

Rule 34(a) states that whistle signals are only required when vessels are in sight of one another and maneuvering as authorized or required by the Rules. Simply backing engines does not constitute a maneuver requiring a whistle signal unless the vessel is actually altering course or changing intent.