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
Most common site of traumatic aoic rupture is 
Select and explain. 
A. Descending thoracic aoa, B. Descending thoracic aoa, C. Arch of aoa, D. Aoic Root
A: Descending thoracic aoa
Answer: A: Descending thoracic aoa 
Explanation: Answer- A. Descending thoracic aoaThe proximal descending aoa, where the relatively mobile aoic arch can move against the fixed descending aoa (ligamentum aeriousm), is at greatest risk from the shearing forces of sudden deceleration. Thus the aoa is a greatest risk in frontalor side impacts, and falls from heights.