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': 'A 55-year old male had retero-sternal discomfort unrelated to physical exertion. Pain gets worse after lying down there is partial relief with antacids. The most likely diagnosis is- \nSelect and explain. \nA. Ischaemic heart disease, B. Carcinoma oesophagus, C. Achalasia cardia, D. Hiatus hernia', 'role': 'user'}, {'content': 'Answer: D \nExplanation: None', 'role': 'assistant'}]