9. Which of the following statements about citric acid cycle is true? (1) Citric acid cycle plays roles in both catabolism and anabolism. (2) All enzymes of the cycle are located in the matrix, except malate dehydrogenase. (3) Both oxidation and decarboxylation reactions are involved in the generation of α-ketoglutarate from isocitrate. (4) The enzyme catalyzed the production of citrate is an allosteric enzyme that is inhibited by NADH, ATP, and succinyl-CoA. (5) The step involves FAD in the citric acid cycle before the step that generates GTP. (A) 1, 2, and 4 are true. (B) 1, 3, 4 and 5 are true. (C) 1, 3, and 4 are true. (D) 1, 2, 3, and 4 are true. (E) All are true.