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': 'Drug which reaches maximum concentration in gingival \nfluid is: \nSelect and explain. \nA. Tetracycline, B. Penicillin, C. Erythromycin, D. Sulphonamide', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]