Final answer:
Medicare Part B covers provider fees without the use of a private insurer, and is the optional insurance system for health-care costs outside hospital stays. It includes physician services, medical tests, and outpatient visits, with the government covering about three-fourths of the costs.
Step-by-step explanation:
The Medicare program consists of several parts, each designed to cover different aspects of a beneficiary's healthcare needs. The part of Medicare that covers provider fees without the use of a private insurer is Part B. Medicare Part B is an optional insurance system that covers healthcare costs outside of hospital stays, including physician services, medical tests, and outpatient visits. Beneficiaries pay a monthly fee, deductible charges, and copayments, while the government covers about 75% of the overall costs. This distinguishes Part B from the other parts of the Medicare program, such as Part A, which pays for some hospital charges; Part C, which allows private health plans to provide Medicare benefits; and Part D, which covers prescription drugs.