The following parts of the ear are involved in hearing EXCEPT

Analyze the question: We need the part of the ear that is not directly involved in the hearing process itself.

Concept: Sound travels through the ear in this order:

1. Pinna collects sound waves.
2. Auditory meatus (ear canal) carries the waves to the eardrum.
3. Eardrum (tympanic membrane) vibrates.
4. Ossicles (malleus, incus, stapes) amplify and transmit the vibrations to the oval window.
5. Cochlea converts the vibrations into nerve impulses, which the auditory nerve carries to the brain.

The eustachian tube connects the middle ear to the pharynx (throat). Its job is to equalise air pressure on both sides of the eardrum, which protects the eardrum and lets it vibrate properly. It is not part of the path sound travels along and does not carry or convert sound.

Checking each option:

• A. Auditory meatus: conducts sound, so it is involved in hearing.
• B. Cochlea: contains the receptors for hearing, so it is involved.
• C. Eardrum: vibrates with sound, so it is involved.
• D. Eustachian tube: pressure equalisation only, so it is not directly involved in hearing.
• E. Ossicles: transmit vibrations, so they are involved.

**Answer: D.

Exam tip: Remember the eustachian tube as the "pressure equaliser". It is the tube you feel "pop" when you swallow or yawn on a plane. Likewise, the semicircular canals are for balance, not hearing, which is another favourite "EXCEPT" option in exams.