This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Surgery
A 30 year old male, labourer, chronic smoker, alcoholic, presents with acute chest pain, severe back pain, radiation to interscapular area. The diagnosis is 
Select and explain. 
A. Myocardial infarction, B. Ruptured aortic aneurysm, C. Pericarditis, D. Tension pneumothorax
B: Ruptured aortic aneurysm
Answer: B: Ruptured aortic aneurysm 
Explanation: (B) Ruptured aortic aneurysm> Dilatations of localised segments of the arterial system are called aneurysms.> They can either be true aneurysms, containing the three layers of the arterial wall in the aneurysm sac, or false aneurysms, having a single layer of fibrous tissue as the wall of the sac, e.g. aneurysm following trauma and as a mycotic aneurysm. ('Mycotic' is a misnomer, as the cause is not due to a fungus but to bacterial infection).