A (Expression Sets); D (Decision Matrix); E (Decision Table). This is the packaged route that keeps the process supportable, auditable, and aligned to the data model.

The Core Concept Explained: Business Rules Engine externalizes decision logic from custom code. Expression Sets orchestrate calculations and can call decision assets so policy thresholds remain maintainable by authorized business users.

Step-by-Step Technical Analysis: Identify the inputs that drive the decision, declare them as Expression Set resources, and use Decision Matrices or Decision Tables where business users must maintain rule thresholds. Execute representative samples before activation, then confirm the output and Decision Explainer history match the expected eligibility, fee, or prioritization result. Expression Sets orchestrate the rule flow and call decision assets.

Why the Incorrect Options Are Wrong: B may look related, but it does not place the logic in the correct declarative Public Sector or OmniStudio configuration layer. C may look related, but it does not place the logic in the correct declarative Public Sector or OmniStudio configuration layer.