<prompt> A new born child has not passed meconium for 48 hours. What is the diagnostic procedure of choice?USGContrast enemaCTMRI  <response>: Failure to pass meconium in the first 2 days of life 48 hours is typically suggestive of a lower GI tract obstruction such as Hirschsprungs diseases, meconium plug syndrome or anorectal malformation. A contrast enema is the most suitable primary investigation to make the diagnosis, amongst the options provided. 