Final answer:
Advertising is a support activity, while the supply of replacement parts is a secondary activity within a company's operations.
Step-by-step explanation:
The question is asking to categorize two different activities within a business context. Advertising is a form of communication with potential customers to promote the sale of a product or service, which does not involve the production or the creation of the core product itself.
Therefore, advertising is considered a support activity, as it supports the primary activities by generating demand and brand awareness. On the other hand, the supply of replacement parts is typically associated with manufacturing, distribution, and after-sales services. It's directly related to the product itself, making it a secondary activity within a business's operations. Hence, the correct answer to fill in the blanks would be: Advertising is a support activity. Supply of replacement parts is a secondary activity.