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': "Among the following, which one is considered as 'pathologic problem' while planning treatment in orthodontics? \nSelect and explain. \nA. Tendency of lower jaw and teeth to be behind upper, B. Deep overbite, C. Minimal attached gingiva in lower anterior region, D. Decalcification", 'role': 'user'}, {'content': 'Answer: C \nExplanation: Inadequate attached gingiva around crowded incisors indicates the possibility of tissue dehiscence developing when the teeth are aligned, especially with non-extraction (arch expansion) treatment.\nproffit page 173', 'role': 'assistant'}]