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': 'Trachoma is caused by which serotype of chlamydia trachomatis? \nSelect and explain. \nA. D to K, B. A, B, C, C. L1 L2 L3, D. All of the above', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. is. 'b' i. e., A, B, C", 'role': 'assistant'}]