A promotion's fundamental purpose is to market or increase sales for specific goods. In the Consumer Goods Cloud data model, the Promotion object is directly linked to the Product2 object via the Promotion Product junction object. This association is critical because it defines what is being promoted. While a promotion is also associated with channels and stores (defining where it runs), the products are the core subject of the campaign, making this the most essential direct association.

A. Retail Store Group: This is a targeting mechanism to define a collection of stores for a promotion. The promotion's core subject remains the product, not the store group.

B. Promotion Channel: This defines the type of outlet (e.g., Supermarket) for the promotion. It is a targeting attribute, not the fundamental subject of the promotion itself.

C. Retail Store: This specifies the exact location for a promotion's execution. The promotion is defined by the products it includes before it is assigned to specific stores.

1. Salesforce Help - Consumer Goods Cloud Data Model: The official data model diagram illustrates the relationships. The Promotion Product object is shown as a junction object with master-detail relationships to both the Promotion and Product2 objects, establishing a direct, many-to-many association.

2. Salesforce Help - Promotions in Consumer Goods Cloud: The documentation defines a promotion as "a time-bound marketing or sales campaign for specific products at specific stores." This highlights that products are a primary component in the definition of a promotion.

3. Salesforce Help - Create a Promotion in Consumer Goods Cloud: The procedural documentation for creating a promotion outlines adding "Tactic Products" as a key step after defining the promotion's basic attributes, reinforcing the centrality of the product association in the business process.