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: Microbiology
[{'content': 'Fever is caused by: \nSelect and explain. \nA. IL 3, B. IL 6, C. IL 5, D. IL 9', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. b. IL 6', 'role': 'assistant'}]