Concept:Federal-level corporations and boards are government-established agencies, while trade associations are private membership bodies.Explanation:FRCN, NNPC, and CBN are all federal corporations or boards set up by the Nigerian government.Manufacturers Association of Nigeria (MAN) is a private trade association of manufacturers, not a federal corporation or board.Therefore, MAN is the option that is NOT a corporation or board at the federal level.Answer:D. MAN