Which of the following practices is considered to be safe for the handling and use of compressed gas cylinders?

Correct Answer: Option C — The storage of the cylinders in a well ventilated compartment.

Compressed gas cylinders must be stored in well-ventilated compartments to prevent the accumulation of hazardous or flammable gases in the event of a slow leak. Proper ventilation is a fundamental safety requirement under 46 CFR and general marine fire prevention standards to mitigate explosion risks in enclosed spaces.