Final answer:
Business rules do not help define the database management system (DBMS) within a data model, but they do contribute to the definition of entities, constraints, and relationships.
Step-by-step explanation:
Business rules play a crucial role in the design and development of a data model. However, what they do not help define within a data model is c.) the database management system (DBMS). Business rules contribute to the establishment of entities, the setting of constraints, and the drawing of relationships between various elements within the data model. On the contrary, the choice of a specific DBMS is a decision that is made based on factors such as performance requirements, cost, and the specific features needed, rather than by the business rules themselves.