Which part of Medicare offers supplemental medical insurance for outpatient services?

Medicare Part B is the component of Medicare that provides supplemental medical insurance specifically for outpatient services. This includes coverage for physician visits, outpatient hospital services, preventive services, and various diagnostic tests. It plays a critical role in ensuring that beneficiaries have access to necessary healthcare services that do not require hospitalization.

In contrast, Medicare Part A primarily covers inpatient hospital stays, hospice care, and some skilled nursing facility care. Medicare Part C, also known as Medicare Advantage, offers a different structure that includes coverage options through private insurance companies, combining the services of Parts A and B, but does not specifically focus on outpatient services alone. Medicare Part D provides coverage for prescription drugs and is not involved in outpatient services either. Thus, Medicare Part B is the correct choice, as it directly addresses the supplemental needs for outpatient medical care.