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
Chemical process involved in conversion of nor-adrenaline to adrenaline ? 
Select and explain. 
A. Hydroxylation, B. Carboxylatio, C. Methylation, D. Dehydrogenatio
C: Methylation
Answer: C: Methylation 
Explanation: Ans. is `c' i.e., Methylation