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': 'Common carcinoma of upper 1/3 oesophagus: \nSelect and explain. \nA. Adenocarcinoma, B. Squamous, C. Squamo columnar, D. Melanoma', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Ans. (b) Squamous cell carcinomaRef: Bailey and love 26th Edition, Page 1004* Most common type of cancer in upper 2/3rd is squamous cell carcinoma.* Most common type of cancer in lower third is adenocarcinoma* Most common type in the world, India: Squamous cell cancer* Most common type in western countries: Adenocarcinoma', 'role': 'assistant'}]