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
Carbonic anhydrase is which type of enzyme ? 
Select and explain. 
A. Coenzyme, B. Metalloenzyme, C. Serine protease, D. Endopeptidase
B: Metalloenzyme
Answer: B: Metalloenzyme 
Explanation: Ans. is 'b' i.e., Metalloenzyme The active site of carbonic anhydrase contains a zinc ion, they are therefore classified as metalloenzymes.