How are 'exclusions' and 'hierarchy' treated in HCC models?

• A. Exclusions remove all HCCs from consideration.
• B. Exclusions apply only to non-Medicare populations.
• C. Hierarchy prevents double counting by summing all overlapping HCCs.
• D. Hierarchy resolves overlapping mappings by counting only the highest-weighted HCC when multiple related codes apply, preventing double counting.

Answer: (D)