Which of the following is NOT a main container type?

• A. Pressure
• B. Cryogenic
• C. Liquid-holding
• D. Gasoline-holding

Answer: (D)

The classification of main container types in hazardous materials primarily encompasses those specifically designed to safely transport or store hazardous substances under varying conditions. Pressure containers are engineered to hold gases or liquids at high pressures; cryogenic containers are meant for substances that must be stored at extremely low temperatures; and liquid-holding containers typically refer to those designed for a variety of liquids, including chemicals and hazardous materials.

Gasoline-holding, however, does not represent a distinct category of container type in the context of hazardous materials management. While gasoline is indeed a hazardous material and can be stored in specialized containers designed for fuel, the term "gasoline-holding" does not convey a standardized container classification recognized within the hazardous materials realm. Instead, gasoline is typically stored in fuel tanks or drums, which fall under the broader classification of combustible liquid containers rather than being a main container type on its own.

Thus, the correct response identifies that "gasoline-holding" is not a main container type in the context discussed.