This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: nutrition and digestion, Subject name: Biochemistry
[{'content': 'Zinc acts as co-factor in \nSelect and explain. \nA. Lactate dehydrogenase, B. Carbonic anhydrase, C. Glutathione peroxidase, D. Alkaline phosphatase', 'role': 'user'}, {'content': 'Answer: A \nExplanation: More than 300 enzymes are zinc-dependent. Some impoant ones are carboxypeptidase, carbonic anhydrase, alkaline phosphatase, lactate dehydrogenase, alcohol dehydrogenase and glutamate dehydrogenase. RNA polymerase contains zinc and so it is required for protein biosynthesis. Extracellular superoxide dismutase is zinc-dependent and so, zinc has antioxidant activity.Ref: DM Vasudevan, page no: 429', 'role': 'assistant'}]