<prompt> Rat tail appearance is seen in?Esophageal carcinomaGastric ulcerAchlasia cardiaCongenital hypertrophic pyloric stenosis  <response>: Ans. is a i.e., Esophageal carcinoma A barium swallow study showing Rat tail sign i.e. narrowing of barium streak at the level of esophagus is a characteristic feature of esophageal carcinoma. 