The biggest decision
These two work very differently. Understanding the difference is most of the work.
Neither one is better in general. They simply suit different people.
Part C
A private plan that takes the place of Original Medicare and bundles your coverage into one plan.
Often fits people who want lower monthly costs and don't mind using a network.
Supplement
Works alongside Original Medicare and helps cover the share Medicare doesn't pay.
Often fits people who travel, see specialists regularly, or value predictable costs.