A developer has business logic in a trigger that flags high-value opportunities.

To adhere to the DRY (Don't Repeat Yourself) principle and ensure maintainability, business logic should be decoupled from specific execution contexts like triggers.

Option C is a best practice. By moving the logic into a Service or Helper class, the code becomes reusable. The trigger can call this class during DML operations to flag records, and an Apex controller (invoked by the Lightning Web Component) can call the same class to retrieve the high-value records for display. This ensures that if the criteria for "high-value" changes, the developer only needs to update the code in one location.

Option D complements this by externalizing the "High Value Amount" threshold. Instead of hardcoding a value (e.g., $100,000) within the Apex code, storing it in Custom Metadata allows administrators to adjust the threshold without requiring a code deployment. The helper class can dynamically query this metadata.

Option A is technically impossible; triggers are fired by the database system in response to DML, not called directly by UI components. Option B leads to "Trigger Bloat" and prevents the LWC from accessing the logic, forcing duplication. Together, C and D provide a scalable, configurable, and reusable architecture.