This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: ENT
Most common cause of conductive deafness in children less than 12yrs: 
Select and explain. 
A. CSOM, B. Otosclerosis, C. Serous otitis media, D. Atresia of auditory canals on both sides
C: Serous otitis media
Answer: C: Serous otitis media 
Explanation: Serous otitis media/secretory otitis media/ mucoid otitis media/glue ear/otitis media with effusion is a condition with accumulation of non-purulent, sterile effusion in the middle ear cleft. It affects children in the age group of 5-8 years. It presents with conductive hearing loss. Fluid level and air bubbles may be seen when the fluid is thin and tympanic membrane transparent. Otosclerosis presents with bilateral conductive hearing loss in the second decade.