What is a primary financial source for Medicare Part B?

The primary financial source for Medicare Part B is beneficiary premiums. These premiums are paid by individuals who enroll in Medicare Part B, which covers outpatient services, physician visits, preventive care, and other medical services not covered by Part A. The funds collected from these premiums are crucial for financing the program, as they help cover the costs of the benefits provided to beneficiaries.

In addition to the premiums paid by enrollees, Medicare Part B is also funded by general revenues from the federal government, but the premiums collected from beneficiaries represent a significant and direct financial contribution to the program. Without these premiums, the program would struggle to sustain operations and provide necessary healthcare services.

Other options, such as state funding, employer contributions, and federal grants, do not play a primary role in financing Medicare Part B. While there may be instances where states support some aspects of healthcare financing or where employers contribute to employee health insurance plans, Medicare Part B primarily relies on the premiums paid by beneficiaries, making this the correct answer.