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: Medicine
[{'content': "A 41/2- year-old girl always had to wear warm socks even is summer season. On physical examination, it was noticed that she had high blood pressure and her femoral pulse was weak as compared to radial and carotid pulse. a chest radiograph showed remarkable notching of ribs along with their lower borders. This was due to - \nSelect and explain. \nA. Femoral artery thrombosis, B. Coarctation of aorta, C. Raynaud's disease, D. Takayasu's arteritis", 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]