Which statement correctly describes how Part D costs are determined?

• A. Premiums only.
• B. Copays only.
• C. Formulary with tiers, copays/coinsurance, and utilization controls like prior authorization.
• D. Enrollment status determines cost.

Answer: (C)

Part D costs for a specific drug come from how the plan prices that drug. The formulary places medications into tiers, and each tier has its own copay or coinsurance amount you pay. In addition, utilization controls such as prior authorization or step therapy can affect whether a drug is covered at all or require you to try alternatives first, which directly changes your out-of-pocket cost. Premiums and thresholds also influence total yearly spending, but the per-drug cost you pay is driven by the formulary tier, the associated cost-sharing, and any utilization-management requirements. That’s why this option best describes how Part D costs are determined.