Final answer:
The maximum capacity for standard ISO intermodal tanks can be up to 26,000 liters, or 6,870 gallons, making option (c) the closest answer with 6,000 gallons (22,700 L).
Step-by-step explanation:
The maximum capacity of an intermodal tank is not clearly specified in the provided material. However, referring to general knowledge outside of the provided context, the capacity of intermodal tanks can vary greatly depending on their purpose and design specifications. For standardized ISO tank containers, which are a common type of intermodal tank, capacities can go up to approximately 26,000 liters (6,870 gallons), which would reflect option (c) 6000 gallons (22, 700 L) as the closest answer.