Final answer:
The surgical operation to correct hearing loss due to defects of the eardrum is tympanoplasty. It involves the repair of the eardrum or the bones in the middle ear to improve hearing. This procedure is often needed when there is a defect in the eardrum or damage to the middle ear bones.
Step-by-step explanation:
The operation performed to correct hearing loss due to defects of the eardrum is D. tympanoplasty. Tympanoplasty is a surgical procedure to repair a perforated eardrum (tympanic membrane) or the small bones in the middle ear which can enhance hearing. Other operations mentioned such as otoplasty, myringotomy, and mastoidectomy are associated with different conditions and are not primarily aimed at repairing the eardrum. For instance, a myringotomy involves making a small incision in the eardrum to relieve pressure caused by excessive buildup of fluid, or to create an opening for a tube to be inserted.
An individual born without the malleus would experience hearing problems because the malleus, along with the incus, transfers the vibrations from the eardrum to the stapes. These vibrations are then transmitted to the cochlea which eventually leads to the perception of sound. Damage to the bones of the middle ear, including the absence of the malleus, can result in conductive hearing loss, which tympanoplasty may address if the eardrum is also affected.