((a)) ** Determination by Commissioner pursuant to agreement between Commissioner and State; costs** The Commissioner of Social Security may enter into an agreement with any State which wishes to do so under which the Commissioner will determine eligibility for medical assistance in the case of aged, blind, or disabled individuals under such State’s plan approved under subchapter XIX. Any such agreement shall provide for payments by the State, for use by the Commissioner of Social Security in carrying out the agreement, of an amount equal to one-half of the cost of carrying out the agreement, but in computing such cost with respect to individuals eligible for benefits under this subchapter, the Commissioner of Social Security shall include only those costs which are additional to the costs incurred in carrying out this subchapter.
((b)) ** Preservation of benefit status for certain disabled widows and widowers**
((1)) An eligible disabled widow or widower (described in paragraph (2)) who is entitled to a widow’s or widower’s insurance benefit based on a disability for any month under section 402(e) or (f) of this title but is not eligible for benefits under this subchapter in that month, and who applies for the protection of this subsection under paragraph (3), shall be deemed for purposes of subchapter XIX to be an individual with respect to whom benefits under this subchapter are paid in that month if he or she—
((A)) has been continuously entitled to such widow’s or widower’s insurance benefits from the first month for which the increase described in paragraph (2)(C) was reflected in such benefits through the month involved, and
((B)) would be eligible for benefits under this subchapter in the month involved if the amount of the increase described in paragraph (2)(C) in his or her widow’s or widower’s insurance benefits, and any subsequent cost-of-living adjustments in such benefits under , were disregarded.
((2)) For purposes of paragraph (1), the term “eligible disabled widow or widower” means an individual who—
((A)) was entitled to a monthly insurance benefit under subchapter II for December 1983,
((B)) was entitled to a widow’s or widower’s insurance benefit based on a disability under section 402(e) or (f) of this title for January 1984 and with respect to whom a benefit under this subchapter was paid in that month, and
((C)) because of the increase in the amount of his or her widow’s or widower’s insurance benefits which resulted from the amendments made by section 134 of the Social Security Amendments of 1983 () (eliminating the additional reduction factor for disabled widows and widowers under age 60), was ineligible for benefits under this subchapter in the first month in which such increase was paid to him or her (and in which a retroactive payment of such increase for prior months was not made).
((3)) This subsection shall only apply to an individual who files a written application for protection under this subsection, in such manner and form as the Commissioner of Social Security may prescribe, no later than .
((4)) For purposes of this subsection, the term “benefits under this subchapter” includes payments of the type described in or of the type described in .
((c)) ** Loss of benefits upon entitlement to child’s insurance benefits based on disability** If any individual who has attained the age of 18 and is receiving benefits under this subchapter on the basis of blindness or a disability which began before he or she attained the age of 22—
((1)) becomes entitled, on or after the effective date of this subsection, to child’s insurance benefits which are payable under on the basis of such disability or to an increase in the amount of the child’s insurance benefits which are so payable, and
((2)) ceases to be eligible for benefits under this subchapter because of such child’s insurance benefits or because of the increase in such child’s insurance benefits,
((d)) ** Retention of medicaid when SSI benefits are lost upon entitlement to early widow’s or widower’s insurance benefits**
((1)) This subsection applies with respect to any person who—
((A)) applies for and obtains benefits under subsection (e) or (f) of (or under any other subsection of if such person is also eligible for benefits under such subsection (e) or (f)) being then not entitled to hospital insurance benefits under part A of subchapter XVIII, and
((B)) is determined to be ineligible (by reason of the receipt of such benefits under ) for supplemental security income benefits under this subchapter or for State supplementary payments of the type described in (or payments of the type described in ).
((2)) For purposes of subchapter XIX, each person with respect to whom this subsection applies—
((A)) shall be deemed to be a recipient of supplemental security income benefits under this subchapter if such person received such a benefit for the month before the month in which such person began to receive a benefit described in paragraph (1)(A), and
((B)) shall be deemed to be a recipient of State supplementary payments of the type referred to in (or payments of the type described in ) if such person received such a payment for the month before the month in which such person began to receive a benefit described in paragraph (1)(A),