Explanation: Upon an accidental VHF-DSC Distress alert, the immediate priority is to stop the erroneous transmission. Most DSC radios will repeatedly transmit the alert until manually stopped, so addressing this first is crucial to prevent further false signals. Following this, an urgent voice announcement must be made on VHF Channel 16. This is the internationally recognized distress, safety, and calling frequency for voice communication. The message, directed to "All Stations," must clearly state the ship's name, call sign, and MMSI, and explicitly cancel the false distress alert. This ensures that all listening vessels and rescue coordination centers are immediately informed, preventing unnecessary responses and resource deployment, as per international maritime radio regulations. Option B is incorrect because there is no standardized DSC message for canceling an initial false alert that is universally understood or capable of overriding the original alert. Option C is dangerously incorrect; failing to cancel a distress alert wastes vital rescue resources. Option D is incorrect as simply turning off power isn't the primary method to stop an alert (which might need to be stopped via menu) and Channel 70 is exclusively for DSC calls, not voice announcements.