Explanation: International maritime regulations, such as those found in the Safety of Life at Sea (SOLAS) convention and the Global Maritime Distress and Safety System (GMDSS), dictate the requirements for emergency power supplies on compulsorily-equipped ship stations. The FCC incorporates these international standards into its own regulations. These rules mandate that the emergency power supply for the emergency radiotelegraph installation (or for general GMDSS distress and safety communication systems in most sea areas) must be capable of providing continuous operation for a minimum period of **6 consecutive hours**. This ensures that critical communication capabilities for distress alerts and safety information remain available during an emergency, even if the ship's main power system fails. The other options are not the specified regulatory minimum for this particular application.