The term working-age individual with a disability receiving Medicaid-funded home or community-based services means a title II disability beneficiary or a title XVI disability beneficiary who has attained age 18, but has not attained age 65, and is receiving home or community-based services— (A) under a waiver approved under subsection (c) or (d) of section 1915 the Social Security Act ( 42 U.S.C. 1396n )