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
Methadone is used in the management of opioid addiction because: 
Select and explain. 
A. Its analgesic activity is less than that of morphine, B. It is an opioid receptor antagonist, C. It is not addictive, D. It is longer acting and causes milder withdrawal symptoms
D: It is longer acting and causes milder withdrawal symptoms
Answer: D: It is longer acting and causes milder withdrawal symptoms 
Explanation: None