This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Thorax, Subject name: Anatomy
[{'content': 'Torus aoicus is \nSelect and explain. \nA. Bulge in the atria, B. Bulge in aoa, C. Aoic wall tear, D. Septal defect', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Torus aoicus is a bulge in the atria . Ref - medscape.com', 'role': 'assistant'}]