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': "Predisposing factors for Esophagus Ca- \nSelect and explain. \nA. Tylosis, B. Achalasia, C. Barrett's esophagus, D. All", 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'a' i.e., Tylosis; 'b' i.e., Achalasia & 'c' i.e., Barrett's esophagus", 'role': 'assistant'}]