What is the outer ear called?
(A) Tympanic membrane
(B) Cochlea
(C) Pinna
(D) Auditory canal

Hint:The listening and balancing organ is the ear.The elements of the external structure of the ear are as:
External or outer ear consist of:
(1) Pinna or auricle
(2) External auditory pathway or tube

Complete step by step answer:
The structure of the ear is as follows:
The outer ear is isolated by the tympanic membrane from the middle one.
The middle ear consists of Ossicles: Ossicles are three thin bones that are interconnected to the inner ear that receives the sound waves. The bones are called:
- Malleus
- Incus
- Stapes
A canal that connects the back of the nose to the middle ear is the Eustachian tube. Around the middle ear, the Eustachian tube helps equalise the pressure. The proper transfer of sound waves needs an equalised pressure. Like the lining of the nose and neck, the Eustachian tube is coated with mucus.
The inner ear consists of
(1) Cochlea: This involves the nerves which helps us in hearing.
(2) Vestibule: It comprises balancing receptors.
(3) Semicircular canals: This also comprises balancing receptors.
Hearing occurs at the outer ear. The sound waves or noises travel through the outer auditory pathway and enter the eardrum if a sound is made outside the external ear. The eardrum vibrates at the sound. The waves are then transferred throughout the middle ear to three tiny bones called the ossicles. They send sound waves to the inner ear.Hence, from the above discussion it can be concluded that option C is correct.

Note:There should not be any confusion as to whether the pinna or the external auditory canal is the outermost ear. The pinna is the outermost structure of the ear. The pinna transmits sound via the auditory canal to the middle ear.