(A) Each county shall have its own county board of developmental disabilities. Subject to division (B) of this section:

(1) A county board shall be operated as a separate administrative and service entity.

(2) The functions of a county board shall not be combined with the functions of any other entity of county government.

(B) Division (A) of this section does not prohibit or restrict any county board from sharing administrative functions or personnel with one or more other county boards, including entering into an arrangement authorized by division (B) of section 5126.0219 of the Revised Code or an agreement with one or more other county boards to share the services of any employee.