(1) An optional unified form of county government shall include either:

    (a) An appointed county manager, who shall comply with the qualifications and exercise the responsibilities detailed in section 7 and 8. This form of county government shall be known as alternate A.

    (b) An elected county executive, who shall comply with the qualifications and exercise the responsibilities detailed in sections 8, 9, 10, and 11. This form of county government shall be known as alternate B.

    (2) A provision of this act not specifically designated as applicable to alternate A or alternate B is applicable to the unified form of county government adopted.