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': 'A Salivary gland tumour, which histologically shows a double layer of epithelial cells based on a reactive lymphoid stroma, is \nSelect and explain. \nA. Pleomorphic adenoma, B. Mucoepidermoid carcinoma, C. Acinic cell tumour, D. Warthin tumour', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]