Which of the following is most likely to cause conductive hearing loss?

Conductive hearing loss occurs when there is a problem in the outer or middle ear that prevents sound from being conducted to the inner ear effectively. One of the most common causes of conductive hearing loss is otitis media, which is an infection or inflammation of the middle ear. This condition can lead to fluid buildup behind the eardrum, blocking the transmission of sound vibrations and causing a decrease in hearing ability.

In this situation, otitis media disrupts the normal functioning of the middle ear structures, such as the ossicles, which are crucial for sound conduction. The resulting hearing loss is often temporary, and it can usually be treated effectively with medical intervention, making it a classic example of conductive hearing loss.

Other options presented, such as presbycusis, are related to sensorineural hearing loss due to aging and damage to the inner ear or auditory pathways. Noise exposure also leads to sensorineural hearing loss, as it can damage hair cells in the cochlea. Birth trauma may result in various hearing impairments, but it does not specifically pinpoint a cause of conductive hearing loss like otitis media does. Thus, otitis media stands out as the clear cause of conductive hearing loss among the provided choices.