What maintenance function may the holder of a GMDSS Radio Operator license perform, or supervise the performance of, on an Inmarsat-C SES?

Correct Answer: Option D — Adjust any front panel controls.

GMDSS Radio Operators are authorized to operate and adjust front panel controls to facilitate communication. However, they are strictly prohibited from performing internal repairs or adjustments to oscillators, synthesizers, or power levels, which require a licensed technician to ensure the equipment remains within FCC and IMO technical type-approval standards.