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
All of the following are used in organophosphorus poisoning except: 
Select and explain. 
A. Pralidoxime, B. Atropine, C. Activated charcoal, D. Naltrexone
D: Naltrexone
Answer: D: Naltrexone 
Explanation: None