<prompt> Retrocardiac lucency with air fluid level is seen inHiatus herniaDistal end esophageal obstructionEventration of diaphragmNone  <response>: Paraoesophageal hiatus herniaRolling herniamay be visible on a plain radiograph of the chest as a gas bubble,often with a fluid level behind the hea.It is herniation of stomach fundus or rarely other abdominal contents through a hiatus,usually towards left side. Reference:Bailey Loves sho practise of surgery,25 th edition,page no:1024;SRBs manual of surgery,5th edition,page no:795. 