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
All of the following enzymes are involved in oxidation - reduction reactions, except 
Select and explain. 
A. Dehydrogenases, B. Hydrolases, C. Oxygenases, D. Peroxidases
B: Hydrolases
Answer: B: Hydrolases 
Explanation: Oxidoreductases (enzymes involved in oxidation - reduction reactions) are : dehydrogenases, oxidases, hydroperoxidases (catalase, peroxidase), oxygenases, reductases and hydroxylases (not hydrolases).