This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Preoperative assessment and monitoring in anaesthesia, Subject name: Anaesthesia
[{'content': 'Most potent antiemetic agent used in preoperative period \nSelect and explain. \nA. Glycopyrolate, B. Hyoscine, C. Atropine, D. Metochlorpromide', 'role': 'user'}, {'content': 'Answer: B \nExplanation: the most potent anti-emetic used is hyoscine . the most commonly used anti-emetics are metochlopramide,ondensetron.', 'role': 'assistant'}]