Explanation: FCC regulations, particularly those outlined in Part 13 for commercial radio operators, allow for flexibility in who performs technical work on lower-power transmitters. For radiotelephone transmitters radiating less than 50 watts carrier power, installation, maintenance, or adjustments can be performed by individuals who do not hold a specific commercial operator license themselves. However, this work *must* be carried out under the immediate supervision and ultimate responsibility of someone holding a higher-grade commercial license: a First Class Radiotelegraph, Second Class Radiotelegraph, or General Radiotelephone Operator License. This ensures proper technical oversight. Options B, C, and D are incorrect. Option B is too restrictive, as supervised work is permitted. Option C (Marine Radio Operator Permit) and Option D (ship radar endorsement) are primarily for operating specific equipment or are highly specialized, and do not grant authority for unsupervised technical work on general radiotelephone transmitters as described.