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': 'Oral submucous fibrosis is diagnosed by \nSelect and explain. \nA. Juxta, epithelial fibrosis (Changes), B. Changes in epithelium, C. Changes in submucosa, D. All of the above', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]