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
Child at birth presented with respiratory distress and drooling of saliva. Mother has a history of polyhydramnios. What is the initial investigation 
Select and explain. 
A. Chest X Ray, B. NG tube and CXR, C. Endoscopy, D. Contrast study
B: NG tube and CXR
Answer: B: NG tube and CXR 
Explanation: This is a case of tracheoesophageal fistula. Initial investigation is inserting nasogastric tube and chest X-Ray. Investigation of choice is IOHEXOL contrast study