Final answer:
The most common cause of conductive hearing loss is impacted cerumen (earwax buildup). This condition is more frequently encountered than other causes such as otosclerosis, cholesteatoma, or chronic serous otitis media. The correct option is C.
Step-by-step explanation:
The Most Common Cause of Conductive Hearing Loss
The most common cause of conductive hearing loss is C. impacted cerumen (earwax buildup).
Conductive hearing loss occurs when there is a problem with the delivery of sound energy to the cochlea, which might be due to blockage of the ear canal, a hole in the tympanic membrane, problems with the ossicles, or fluid in the space between the eardrum and cochlea.
Among the listed options, impacted cerumen is more commonly encountered in the general population than the other conditions, which are less prevalent but can also cause conductive hearing loss.
Otosclerosis (Option A) involves the abnormal growth of bone in the middle ear, which can prevent the ossicles from vibrating properly. A cholesteatoma (Option B) is an abnormal skin growth in the middle ear behind the eardrum.
Chronic serous otitis media (Option D) refers to persistent fluid accumulation in the middle ear, which can also affect conductive hearing. While each of these conditions can lead to conductive hearing loss, impacted cerumen is the condition that most frequently necessitates medical attention or intervention for hearing impairment.