Which of the following services is not covered by Medicare Part B?

Medicare Part B primarily covers services that are medically necessary for diagnosis and treatment, which includes outpatient physician visits, durable medical equipment, and various outpatient laboratory and radiology tests. However, routine vision and dental care, including eyeglasses and routine dental care, are not included in the coverage under Medicare Part B.

The exclusion of eyeglasses and routine dental care is based on Medicare's design, which focuses on essential medical services rather than preventive or routine services that are often considered part of overall health maintenance. This reflects Medicare's intent to provide coverage mainly for critical medical conditions and treatments rather than preventive or elective procedures. Consequently, this stipulation leads to the conclusion that eyeglasses and routine dental care do not qualify for coverage under Part B.