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
Enzyme regulating the conversion of ethanol to acetaldehyde: 
Select and explain. 
A. Alcohol dehydrogenase, B. Acetaldehyde dehydrogenase, C. Catalase, D. Enolase
A: Alcohol dehydrogenase
Answer: A: Alcohol dehydrogenase 
Explanation: None