<prompt> Marions disease is due to:Muscular hypertrophy of internal sphincter of urinary bladderFibrosis of the neck of bladderVesicular diverticulaVesicular calculi  <response>: Ans. a Muscular hypertrophy of internal sphincter of urinary bladder Congenital hypertrophy of the posterior urethra due to muscular hypertrophy and stenosis at bladder neck is known as Marions disease. 