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: Pharmacology
In metabolism of xenobiotics, all of the following reactions occur in phase one except: 
Select and explain. 
A. Oxidation, B. Reduction, C. Conjugation, D. Hydrolysis
C: Conjugation
Answer: C: Conjugation 
Explanation: Metabolic reactions may be classified into phase I (non-synthetic) and phase II (synthetic) reactions. Phase I reactions include oxidation, reduction, hydrolysis, cyclization and decylization etc. whereas phase II reactions include glucuronidation, acetylation,methylation, sulfation and glycine conjugation etc.