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
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- 
Select and explain. 
A. Ischaemic heart disease, B. Carcinoma oesophagus, C. Achalasia cardia, D. Hiatus hernia
D: Hiatus hernia
Answer: D: Hiatus hernia 
Explanation: None