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': 'Plummer- Vinson syndrome \nSelect and explain. \nA. Is due to folic acid deficiency, B. Common in males, C. Not associated with oral premalignancy, D. Strong association with post-cricoid carcinoma', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]