Which of the following rule types is NOT a declarative rule type?

Declare Activities is indeed not a declarative rule type. Declarative rules in Pega are designed to automatically maintain and recalculate data, applying business logic without requiring explicit intervention in the process. The primary purpose of declarative rules is to enhance efficiency and ensure data integrity by automatically adjusting data as underlying values change.

Constraints, Declare Expressions, and Declare Constraints all exemplify declarative rules. Constraints focus on enforcing conditions on properties to ensure that they meet specific requirements. Declare Expressions enable calculations that automatically update field values or properties based on rule conditions, while Declare Constraints set rules around the relationships between properties.

In contrast, Declare Activities is classified as a procedural rule type. It requires step-by-step execution and user-defined logic based on specific conditions or actions within a given process. This proactive handling of activities differentiates it from the automatic recalibration inherent in the other declarative rule types. Thus, understanding the distinction between declarative and procedural rules is essential for Pega Business Architects and highlights the functional differences in how these rules operate within the Pega system.