Which of the following is NOT one of the four major container types?

• A. Pressure
• B. Cryogenic
• C. Liquid Holding
• D. Gas Holding

Answer: (D)

The concept being tested is how hazmat packaging is categorized by container design. In this framework, containers are grouped by how they contain materials under various conditions: pressure containers are built to withstand internal pressures, cryogenic containers are for materials kept at extremely low temperatures, and liquid-holding containers are used for liquids that aren’t stored under pressure. Gas holding isn’t treated as a separate category because gases are shipped in pressure-rated vessels or in configurations that fall under the pressure container category rather than forming a distinct “gas holding” type. So the first three options fit the recognized container types, while gas holding isn’t considered its own major type.