This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Oesophagus, Subject name: Surgery
[{'content': "Tumor seen in Barret's Esophagus \nSelect and explain. \nA. Adenocarcinoma, B. Squamous cell cancer, C. Melanoma, D. Basal Cell Carcinoma", 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. (a) AdenocarcinomaRef: Surgery Sixer 3rd Edition Page 330Predisposing factors of Esophageal Adenocarcinoma:* GERD* Barret's Esophagus* Obesity* Scleroderma* High Protein Diet and Fat Diet* SmokingNote: H. pylori producing cag -A toxin is protective against Adenocarcinoma of Esophagus", 'role': 'assistant'}]