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: Radiology
Rib notching is seen in all the following except: 
Select and explain. 
A. Blalock-Taussing shunt, B. Coarctation of the aoa, C. TVC obstruction, D. None
D: None
Answer: D: None 
Explanation: Ans. None