This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anaesthesia, Subject name: Pharmacology
[{'content': 'Dissociative anesthesia is seen with which drug: \nSelect and explain. \nA. Ketamine, B. Fentanyl, C. Propofol, D. Nitrous oxide', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. A. KetamineKetamine is NMDA receptor antagonist, they are strong analgesic with no muscle relaxant property. It is used to create dissociative anesthesia in which patient dissociate from one own body.', 'role': 'assistant'}]