Final answer:
Medicare Part D plans do not have to cover MTM services, but many plans offer this benefit to members.
Step-by-step explanation:
Medicare Part D plans are prescription drug plans offered by private insurance companies approved by Medicare. These plans must follow certain guidelines set by Medicare, but the coverage they provide can vary. Medication Therapy Management (MTM) services are not mandatory for Medicare Part D plans, but many plans do offer MTM services as an added benefit to their members. MTM services help optimize medication use and improve health outcomes for individuals taking multiple medications or with chronic health conditions.