5. Which of the following descriptions about "regulating of enzyme activity in metabolism" is INCORRECT? (A) Allosteric regulation is the term used to describe any case in which a protein’s function at one site is affected by the binding of a regulatory molecule to a separate site. (B) An activating or inhibiting regulatory molecule binds to a regulatory site that is the simplest kind of allosteric regulation. (C) Feedback inhibition is a common mode of metabolic control. (D) Cooperativity is a type of enzyme activation, not including inhibition. (E) Cooperativity is the binding of one substrate molecule that can stimulate binding or activity at other active sites.