<prompt> Mercedes Benz sign or Seagull sign is seen in:GallstonesRenal stonesCBD stonesHydatid cyst  <response>: Mercedes Benz sign or Seagull sign The centre of Gallstone may contain radiolucent gas in a triradiate or biradiate fissure, this gives rise to characteristic darkshapes on radiograph- the Mercedes Benz sign or Seagull sign. 