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: Pathology
[{'content': 'Prolonged administration of broad spectrum antibiotics results in the formation of: \nSelect and explain. \nA. Black hairy tongue, B. Median rhomboid glossitis, C. Geographic tongue, D. Fissured tongue', 'role': 'user'}, {'content': 'Answer: A \nExplanation: None', 'role': 'assistant'}]