Define 'beneficiary' in the context of Medicare.

In the context of Medicare, a beneficiary refers specifically to an individual who is enrolled in a Medicare plan. This means the person has met the eligibility requirements set forth by Medicare, which generally includes being aged 65 or older, or being under 65 with certain disabilities, or having specific conditions such as End-Stage Renal Disease (ESRD) or Amyotrophic Lateral Sclerosis (ALS).

Being a beneficiary allows individuals access to various Medicare benefits, such as hospital insurance (Part A), medical insurance (Part B), and prescription drug coverage (Part D). Understanding who qualifies as a beneficiary is essential for comprehending Medicare policies, coverage options, and the rights afforded to those enrolled in the program.

The other options do not accurately reflect the definition of a beneficiary under Medicare. For instance, being eligible for Medicaid concerns a different program aimed at low-income individuals and families, while the roles of caregivers and service providers, although integral to the healthcare system, pertain to different aspects that do not define the individual who is receiving benefits from Medicare.