17. Which of the following is TRUE regarding cofactors?
(A) Coenzymes are often separate from the enzyme and do not need recharged.
(B) Metal ions must be covalently attached to function as a cofactor.
(C) Cofactor is a broad term used for all enzyme "helpers".
(D) Prosthetic groups can dissociate readily and be regenerated for use in another enzyme.
(E) An apoenzyme implies that a cofactor is present.