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': 'Ketamine is preferred anaesthetic agent in the following cases except \nSelect and explain. \nA. Cyanotic congenital heart disease, B. Hypertension, C. Shock, D. Asthmatic patients', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Since ketamine stimulates sympathetic nervous system, it causes hypertension and tachycardia.', 'role': 'assistant'}]