This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Ear, Subject name: ENT
Cause of myringosclerosis is 
Select and explain. 
A. Genetic, B. Grommet inseion, C. Otosclerosis, D. Idiopathic
B: Grommet inseion
Answer: B: Grommet inseion 
Explanation: Grommet inseion is preferred if myringotomy and aspiration combined with medical measures have not helped and fluid recurs, a grommet is inseed to provide continued aeration of the middle ear. It is left in place for weeks or months or till it is spontaneously extruded. Ref - PL DHINGRA diseases of ear nose and throat, 6th edition, page no 65