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': 'If the distance between the tip of tongue and insertion of lingual frenum is 6 mm, then it will be: \nSelect and explain. \nA. Mild ankyloglossia, B. Moderate ankyloglossia, C. Severe ankyloglossia, D. Complete ankyloglossia', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Class 1 - Mild ankyloglossia - 12-15 mm\nClass 2 - Moderate ankyloglossia - 8-11 mm\nClass 3 - Severe ankyloglossia - 4-7 mm\nClass 4 - Complete ankyloglossia - 0-3 mm.', 'role': 'assistant'}]