This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Enzymes, Subject name: Biochemistry
[{'content': 'Zn is present as prosthetic group in this enzyme: \nSelect and explain. \nA. Carbonic anhydrase, B. Carboxy peptidase, C. Lactate dehydrogenase, D. All of these', 'role': 'user'}, {'content': 'Answer: D \nExplanation: Ans. D. All of theseAll enzymes are proteins. It consists of a protein part and a non-protein part. If a non-protein part is a metal ion it becomes a co-factor. If a non-protein part is an organic molecule it becomes a co-enzyme. Zinc is a co factor of so many biochemical reactions.', 'role': 'assistant'}]