12. Which one of the following statements about gluconeogenesis is false? (A) For starting materials, it can use carbon skeletons derived from certain amino acids. (B) It consists entirely of the reactions of glycolysis, operating in the reverse direction. (C) It employs the enzyme glucose 6-phosphatase. (D) It is one of the ways that mammals maintain normal blood glucose levels between meals. (E) It requires metabolic energy (ATP or GTP).