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': 'Lingual plate is indicated in all, except \nSelect and explain. \nA. Periodontally weakened tooth, B. Anterior ridge resorption, C. High Lingual frenum, D. Vestibule of more than 8 mm', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]