Final answer:
In an assembly server food service system, frozen bulk pudding would be purchased as it is efficient and cost-effective for serving large numbers of people compared to instant, canned, or individual portions.
Step-by-step explanation:
The question asks which form of pudding would be purchased in an assembly server food service system. An assembly serve system is a food service operation in which menu items are purchased prepared and require minimal cooking before service.
The most efficient option for this type of system would be frozen bulk pudding.
This is because frozen bulk products can be bought in large quantities, stored easily, and prepared with minimal effort. They are also more cost-effective for serving large numbers of people. Other forms like instant, canned, or individual portions may require more packaging and preparation time which might not be suitable for an assembly serve system's emphasis on efficiency and volume.