to accept assignment under section 1842(b)(3)(B)(ii) of the Social Security Act [42 U.S.C. 1395u
(b)(3)(B)(ii)] for all services for which payment may be made under part B of title XVIII of such Act [42 U.S.C. 1395j
et seq.], and to enter into an appropriate agreement with the State agency that administers the State plan for medical assistance under title XIX of such Act [42 U.S.C. 1396
et seq.] to provide service to individuals entitled to medical assistance under the plan.