The area of the board shall consist of all of the following:
(a) The Cities of Chula Vista, Coronado, El Cajon, Imperial Beach, La Mesa, Lemon Grove, National City, Poway, San Diego, and Santee.
(b) All of the unincorporated area of the County of San Diego, except as otherwise included within the North San Diego County Transit Development Board in Section 125052.
(c) All the unincorporated area of the County of San Diego surrounded by the cities specified in subdivisions (a) and (b).