What eligibility requirement must Mrs. Russo meet to enroll in a Medicare prescription drug plan?

To enroll in a Medicare prescription drug plan, a beneficiary must be entitled to Medicare Part A. This entitlement indicates that the individual has satisfied the necessary criteria to receive Medicare benefits, which include hospital insurance that is primarily part of Medicare coverage. While being enrolled in Part B is also important for broader Medicare coverage, it is not a strict requirement for enrolling in a standalone Part D prescription drug plan. Therefore, entitlement to Part A is a crucial eligibility criterion essential for any Medicare beneficiary seeking to add prescription drug coverage to their benefits.

Having an employer retiree plan or being previously enrolled in another drug plan does not disqualify or qualify Mrs. Russo for enrolling in a Medicare prescription drug plan, as these factors do not directly tie into the fundamental eligibility criteria established by Medicare. Thus, the focus is on the entitlement to Part A when discussing basic eligibility for these plans.