In the United States, Medicare is a national health insurance program, now administered by the Centers for Medicaid and Medicare Services of the U.S. federal government but begun in 1966 under the Social Security Administration. United States Medicare is funded by a combination of a payroll tax, premiums and surtaxes from beneficiaries, and general revenue. It provides health insurance for Americans aged 65 and older who have worked and paid into the system through the payroll tax. It also provides health insurance to younger people with some disability status as determined by the Social Security Administration, as well as people with end stage renal disease and amyotrophic lateral sclerosis.

What tax is used to provide medical services for persons over the age of 65? OK. Let's think. My stream of consciousness:
The relevant information to answer the above question is: It provides health insurance for Americans aged 65 and older who have worked and paid into the system through the payroll tax. The answer is the payroll tax.