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: Surgery
[{'content': "The adenocarcinoma of esophagus-develops in - \nSelect and explain. \nA. Barret's esophagus, B. Long standing achalasia, C. Corrosive stricture, D. Alcohol abuse", 'role': 'user'}, {'content': "Answer: A \nExplanation: Adenocarcinoma of esophagus almost always arises in Barrett's esophagus.\nOther option i.e. long standing achalasia, corrosive stricture and alcohol abuse are risk factors for squamous cell Ca of esophagus", 'role': 'assistant'}]