(b)
The Secretary shall approve any plan which fulfills the conditions specified in subsection (a) of this section, except that he shall not approve any plan which imposes, as a condition of eligibility for aid to the permanently and totally disabled under the plan—
(1)
Any residence requirement which excludes any resident of the State who has resided therein five years during the nine years immediately preceding the application for aid to the permanently and totally disabled and has resided therein continuously for one year immediately preceding the application;
(2)
Any citizenship requirement which excludes any citizen of the United States.
At the option of the State, the plan may provide that manuals and other policy issuances will be furnished to persons without charge for the reasonable cost of such materials, but such provision shall not be required by the Secretary as a condition for the approval of such plan under this subchapter.