Who has ultimate control of service at a ship's radio station?

The master of the ship holds ultimate control of service at a ship's radio station because he or she is responsible for the overall safety and navigation of the vessel. This responsibility encompasses all operational components on board, including communications. The master ensures compliance with maritime laws, regulations, and safety protocols, which includes overseeing radio communications and delegating responsibilities to qualified personnel, such as the radio officer. This hierarchical structure is crucial for maintaining clear command authority and ensuring efficient emergency response, as the master can make decisive choices in critical situations.

Other options, while they pertain to individuals authorized to operate the radio equipment, do not hold the overarching command that the master has. The Radio Officer-in-Charge, for example, may manage the daily operations of the radio station but still operates under the authority of the master. Similarly, others who may hold licenses or certifications to operate the radio station have specific duties but do not encompass the full responsibility for the ship’s operations like the master does. Thus, ultimate control rests with the master of the ship.