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: Anaesthesia
The following are used for treatment of postoperative nausea and vomiting following squint surgery in children except – 
Select and explain. 
A. Ketamine, B. Ondansetron, C. Propofol, D. Dexamethasone
A: Ketamine
Answer: A: Ketamine 
Explanation: None