Answer is C (Nasogastric tube inseion ) : The ideal next step is to confirm the position of ET tube and / or Remove the tube and reattempt intubation, if the tube is not in the trachea. 'Removal of tube and reattempting intubation' is not provided amongst the option and position of the ET tube cannot be confirmed by chest X-ray. As both these possibilities are not provided in the list of options, the next best step is to decompress the bowel by nasogastric tube inseion and aspiration. This would help in relieving some respiratory distress and is therefore the single best answer of choice amongst the options provided. X-Ray chest should be next step after nasogastric tube inseion to confirm the diagnosis, followed by surgery once the patient has been resuscitated, investigated and stabilized.