To enroll in Medicare Part D prescription drug coverage, a beneficiary must:

Why A is correct

Medicare Part D eligibility requires the beneficiary to be entitled to Medicare Part A and/or enrolled in Medicare Part B. Because Part D is a voluntary benefit open to people already in the Medicare program, the Part A and/or Part B requirement is the sole eligibility gate. Age and employment status are irrelevant to Part D eligibility, and neither exhaustion of Part A reserve days nor the purchase of a Medigap policy is required. Option A correctly states the eligibility condition for Part D enrollment.

Why the other options are wrong

• B) Part D is available to Medicare beneficiaries regardless of age or work status; being under 65 and working describes the wrong population for Part D eligibility. Part D eligibility is defined by Medicare entitlement, not by age or employment status.
• C) Lifetime reserve days concern Part A hospitalization after day 90 within a benefit period; exhausting them has nothing to do with Part D enrollment eligibility. Lifetime reserve days are a Part A hospitalization feature and are irrelevant to Part D.
• D) Medigap is a separate product and is not a prerequisite; many beneficiaries enroll in Part D without ever purchasing a Medigap policy. Medigap is never a prerequisite for enrolling in the Part D program.

Memory hook

Part D's only ticket: Part A and/or Part B. No age test, no Medigap test, no reserve-day test.

Why A is correct

Part D enrollment is tied to Medicare entitlement: a beneficiary must have Part A and/or be enrolled in Part B to join a stand-alone Prescription Drug Plan or a Medicare Advantage plan with drug coverage. This linkage is the basic eligibility gate for Part D. Age 80, home ownership, and disability are all irrelevant to Part D eligibility — someone under 65 can enroll if entitled to Part A through a disability, and a 65-year-old with Part A and B is eligible regardless of housing status or disability documentation.

Why the other options are wrong

• B) Part D eligibility is not age-80-gated; any Medicare-entitled beneficiary can enroll.
• C) Home ownership has no bearing on Part D eligibility.
• D) Disability matters only as a route to Part A entitlement, not as a standalone Part D requirement.

Memory hook

Part D needs a foot in Medicare's door — Part A or Part B.