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-a)  Tylosisb)  Achalasiac) Barrett's esophagus d)  Scleroderma \nSelect and explain. \nA. ab, B. bc, C. abc, D. bcd", 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]