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: Dental
[{'content': 'Laboratory test of ANUG is: \nSelect and explain. \nA. Complement fixation, B. Dark field examination, C. Tissue culture, D. Animal inoculation', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]