What is the meaning of "Reserve Source of Energy"?

Correct Answer: Option A — The supply of electrical energy sufficient to operate the radio installations for the purpose of conducting Distress and Safety communications in the event of failure of the ship's main and emergency sources of electrical power.

The Reserve Source of Energy is defined as an independent electrical supply, typically battery banks, designed to power GMDSS radio installations for a specified duration during a failure of both the ship's main and emergency generators. This ensures continuous distress alerting and safety communication capabilities during critical emergencies.