9. A new compound isolated from mitochondria is claimed to represent a previously unrecognized carrier in the electron transfer chain. It is given the name coenzyme Z. Which line of evidence do you feel is the least conclusive in assigning this compound a position in the electron transfer chain? (A) Alternate oxidation and reduction of the mitochondrion-bound coenzyme Z can be readily demonstrated. (B) Removal of coenzyme Z from the mitochondria results in a decreased rate of oxygen consumption. (C) The rate of oxidation and reduction of mitochondrion-bound coenzyme is of the same order of magnitude as the overall rate of electron transfer in mitochondria as measured by oxygen consumption. (D) The reduction potential of Z is between that of two compounds known to participate in the electron transport chain. (E) When added to a mitochondrial suspension, coenzyme Z is taken up very rapidly and specifically by the mitochondria.