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
Zinc is a cofactor for: 
Select and explain. 
A. Pyruvate dehydrogenase, B. Pyruvate decarboxylase, C. a-keto glutarate dehydrogenase, D. Alcohol dehydrogenase
D: Alcohol dehydrogenase
Answer: D: Alcohol dehydrogenase 
Explanation: Alcohol dehydrogenase Zinc containing enzymes are: 1) Superoxide dismutase (it is a Cu-Zn protein complex) 2) Carbonic anhydrase 3) Leucine amino peptidase 4) Carboxy peptides 'A' 5) Alcohol dehydrogenase 6) Retinine reductase 7) Alkaline phosphatase 8) Glutamate dehydrogenase 9) Lactate dehydrogenase 10) DNA and RNA polymerase 11) d-ALA dehydratase