This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Complications Of Anaesthesia, Subject name: Anaesthesia
[{'content': 'Anaphylaxis is caused by - \nSelect and explain. \nA. N2O, B. Althesin, C. Halothane, D. Propofol', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is 'b' i.e., Aithesin Althesino Althesis is a neurosteriodo It was used as a parenteral anaesthetico It was withdrawn from the market because of several severe anaphylactic reactions", 'role': 'assistant'}]