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': 'Weil-Felix reaction positive with OXK antigen in: \nSelect and explain. \nA. Trench fever, B. Scrub typhus, C. Endemic typhus, D. Epidemic typhus', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is. 'b' i. e., Scrub typhus", 'role': 'assistant'}]