This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
[{'content': 'Zinc is a cofactor of \nSelect and explain. \nA. Alcohol dehydrogenase, B. Pyruvate Carboxylase, C. Pyruvate oxidase, D. None of the above', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Metalloenzymes: These enzymes hold the metals rather tightly which are not readily exchanged.\xa0\nAlcohol dehydrogenase, carbonic anhydrase, alkaline phosphatase, carboxypeptidase and aldolase contain zinc.\nPhenol oxidase (copper); Pyruvate oxidase (manganese); Xanthine oxidase (molybdenum); Cytochrome oxidase (iron and copper).\nSatyanrayana, Ed 3, page no 91', 'role': 'assistant'}]