<prompt> Which of the following is not a derivative of the middle ear cleft-Semicircular canalMastoid aircellTympanic cavityEustachian tube  <response>: Ans. is a i.e., Semicircular canal o The middle - ear cleft in the temporal bone includesEustachian tubeThe middle ear tympanic cavityAditus wrhich leads posteriorly to the mastoid antrum and air cells. 