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
[{'content': 'Increased Cardiac Oxygen demand is caused by \nSelect and explain. \nA. Halothane, B. Thiopentone, C. N20, D. Ketamine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: D i.e. Ketamine', 'role': 'assistant'}]