This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Intravenous Anesthetic Agents, Subject name: Anaesthesia
Which is the intravenous anesthetic agent contributing in good analgesia:- 
Select and explain. 
A. Thiopentone, B. Propofol, C. Etomidate, D. Ketamine
D: Ketamine
Answer: D: Ketamine 
Explanation: Ketamine produces very good analgesia. Ketamine can be used to reduce post operative pain as it produces profound analgesia. It inhibits nociceptive central hypersensitization. Besides, ketamine may be effective in the treatment of cancer pain, chronic neuropathic pain, phantom limb pain, fibromyalgia, complex regional pain syndrome, visceral pain, and migraine.