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: Pediatrics
A 1-month-old boy is referred for failure to thrive. On examination, he shows feature of congestive failure. The femoral pulses are feeble as compared to branchial pulses. The most likely clinical diagnosis is: 
Select and explain. 
A. Congenital aoic stenosis, B. Coarctation of aoa, C. Patent ductus aeriosus, D. Congenital aooiliac disease
B: Coarctation of aoa
Answer: B: Coarctation of aoa 
Explanation: Feeble femoral pulsations compared to strong brachial pulsations suggests the diagnosis of coarctation of aoa. Hypeension and strong pulsations in the upper extremities and absence, marked dimunition or delay in pulsations in the femoral aery are characteristic in coarctation. Coarctation of aoa may result in congestive hea failure in infancy. Ref: Essential Pediatrics, 6th Edition By O P Ghai, Pages 419-20.