Final answer:
The answer is option B. The custom field type that should be used is an auto-number field.
Step-by-step explanation:
The custom field type that should be used to meet the requirements of Prestige Worldwide's order management system is (b) An auto-number field. An auto-number field automatically assigns a unique and incrementing number to each record. In this case, the auto-number field should be set up to generate a 6-digit number that starts with the prefix 'ORD-', ensuring the uniqueness of each order.
An auto-number field automatically assigns a unique and incrementing number to each record. In this case, the auto-number field should be set up to generate a 6-digit number that starts with the prefix 'ORD-', ensuring the uniqueness of each order.