Educational service agency means—

(a) A regional public multiservice agency—

(1) Authorized by State law to develop, manage, and provide services or programs to LEAs;

(2) Recognized as an administrative agency for purposes of the provision of special education and related services provided within public elementary schools and secondary schools of the State;

(b) Includes any other public institution or agency having administrative control and direction over a public elementary school or secondary school; and

(c) Includes entities that meet the definition of intermediate educational unit in section 602(23) of the Act as in effect prior to June 4, 1997.