Final answer:
Bridge alarms are the system that signals override microphone control stations to notify the ship's crew of imminent danger in various emergency situations.
Step-by-step explanation:
The system that signals override microphone control stations to notify the ship's crew of imminent danger is the Bridge alarms. These alarms are designed to alert the crew in various emergency situations such as collision, chemical attack, general alarms, and flight crash. They provide loud audible signals and may also include visual indicators to ensure that the crew is aware of the emergency situation.