(a) “Credit hour” means the basic unit of collegiate level instruction, as determined by the state board, in a subject or course offered at a level not higher than those subjects or courses normally offered to freshmen and sophomores in four-year institutions of postsecondary education which subject or course is approved by the state board.

(b) The term “credit hour” does not include instruction in a subject or course taken by a student enrolled for audit or in any subject or course not approved by the state board.

(c) The state board shall determine whether the subjects and courses offered in the community colleges are at the level of freshmen and sophomore subjects and courses offered in the state educational institutions and shall not approve for funding any subject or course offered at a higher level.