This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Carbohydrates, Subject name: Biochemistry
Which is true for glucuronidation: 
Select and explain. 
A. Water solubility is decreased, B. Phase II reaction, C. Phase I reaction, D. Done by CYP enzyme
B: Phase II reaction
Answer: B: Phase II reaction 
Explanation: Ans. (b) Phase II reactionRef: Harper's Biochemistry, 30 edn. pg. 586 thMETABOLISM OF XENOBIOTICS* In phase 1, the major reaction involved is hydroxylation, catalyzed by enzymes mono-oxygenases or cytochrome P450s. The reactions are:* Hydroxylation# Deamination# Dehalogenation# Desulfuration# Epoxidation# Peroxygenation# Reduction* In phase 2, compounds produced in phase 1 are converted to various polar metabolites by conjugationwith glucuronic acid, sulfate, acetate, glutathione, or certain amino acids, or by methylation.* The overall purpose of the two phases of metabolism of xenobiotics is to increase their water solubility (polarity) and thus excretion from the body.Glucuronidation: UDP Glucuronic acid is the glucuronyl donor, and a variety of glucuronosyl transferases, present in both the endoplasmic reticulum and cytosol, are the catalysts.* Phase II reactions are:# Glucuronidation: is probably the most frequent conjugation reaction.# Sulfation# Conjugation with Glutathione# Acetylation# Methylation