The Bottom Line (Direct Answer): Answer: C, D, E — C (Add the Decision Explainer Log History component to..); D (Integrate the BRE with Decision Explainer.); E (Assign the Decision Explainer Permissions Set License..). This maps the scenario to the Salesforce-native capability that owns the requirement.

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. Integrate BRE with Decision Explainer, add the Decision Explainer Log History component to the relevant Lightning record pages, and assign the Decision Explainer permission set license to the appropriate users.

Why the Incorrect Options Are Wrong: A can orchestrate work, but it is not the preferred rule-decision asset for maintainable fee, eligibility, or prioritization logic. B adds a custom build path and increases lifecycle, security, and upgrade effort when a packaged or declarative capability already supports the requirement.