The mandatory Medicaid service that states must offer to receive federal matching funds is the Medicare. That is option D.
Medicare is defined a health insurance program offered in US that helps in subsidizing funds for health care services.
Medicaid service is a joint program involving both federal and state government which helps to provide low cost or free health care services to the citizens.
It is a mandatory service that must cover services specific to the federal law to be able to receive federal matching funds.
Learn more about Medicaid service here:
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