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 discomfo unrelated to physical exeion. Pain gets worse after lying down there is paial relief with antacids. The most likely diagnosis is- 
Select and explain. 
A. Ischaemic hea disease, B. Carcinoma oesophagus, C. Achalasia cardia, D. Hiatus hernia
D: Hiatus hernia
Answer: D: Hiatus hernia 
Explanation: Ans. is 'd' i.e., Hiatus hernia