Which type of Marine Sanitation Device (MSD) is used solely for the storage of sewage and flush water at ambient air pressure and temperature?

Correct Answer: Option C — Type III

33 CFR 159.3 defines a Type III Marine Sanitation Device as a holding tank system. It provides no treatment, serving solely for the temporary storage of sewage and flush water at ambient pressure and temperature until it can be discharged ashore or in legal waters.