Which of the following compressors would be used for a cold-ship start-up of a ship's service diesel generator on a motor ship?

Correct Answer: Option D — Emergency air compressor

Emergency air compressors are independent units, often powered by a dedicated diesel engine or battery-backed motor. They are specifically designed to provide a source of compressed air for starting a ship's service diesel generator when no other air is available, enabling a 'black start' of the vessel's power plant.