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 term newborn presents with frothing, excessive drooling of saliva, coughing of saliva. There was history of polyhydramnios in antenatal period. There is difficulty in passing a  nasogastric tube. What is the probable diagnosis? 
Select and explain. 
A. Diaphragmatic hernia, B. Choanal atresia, C. Gastroschisis, D. Tracheo-esophageal fistula
D: Tracheo-esophageal fistula
Answer: D: Tracheo-esophageal fistula 
Explanation: Tracheo-esophageal fistula :

Newborn presents with frothing, excessive salivation.
Associated with polyhydramnios in antenatal period.
Nasogastric tube is inserted and inability to pass it confirms the diagnosis of TEF.