What is required for participation in Medicare - Part C?

To participate in Medicare Part C, also known as Medicare Advantage, individuals must first be enrolled in both Medicare Part A and Part B. This requirement ensures that beneficiaries have access to the full range of services provided by Medicare, as Part C plans are designed to offer additional coverage beyond what is provided by Parts A and B. By integrating and substituting the original Medicare benefits, Part C plans allow beneficiaries to receive their healthcare through private insurance companies that are approved by Medicare.

As for the other options, they do not accurately reflect the prerequisites for enrollment in Medicare Part C. Automatic enrollment without prerequisites misunderstands the necessary steps for joining Part C. While some plans may offer benefits without the need for prior coverage, a Medigap plan is not a substitute for the prerequisite of enrolling in Part A and Part B. Lastly, the idea that no prior insurance plan is necessary does not apply here, as the participation in Medicare Part C specifically requires the foundational Medicare coverage of Parts A and B.