Which of the following predictions is a plausible explanation for how ADP activates isocitrate dehydrogenase?A. When binding to isocitrate dehydrogenase, ADP decreases the Km for isocitrate.B.When binding to isocitrate dehydrogenase, ADP increases the Km for isocitrate.C. When binding to isocitrate dehydrogenase, ADP dephosphorylates the enzyme.D. When binding to isocitrate dehydrogenase, ADP phosphorylates the enzyme.