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: Pathology
Which is the most preferred route for drug administration in the management of chronic pain 
Select and explain. 
A. Intrathecal, B. Oral, C. Subdermal, D. Intravenous
B: Oral
Answer: B: Oral 
Explanation: None