This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Mechanisms of Enzyme Action, Subject name: Biochemistry
Zinc is essential for - 
Select and explain. 
A. Pyruvate lrinase, B. Cytochrome oxidase, C. Xanthine oxidase, D. Carbonic anhydrase
D: Carbonic anhydrase
Answer: D: Carbonic anhydrase 
Explanation: Ans. is 'd' i.e., Carbonic anhydrase