Question

The three parts of the human ear contributing to hearing are
A) cochlea, ear ossicles and tympanum
B) semicircular canals, utriculus and sacculus
C) Eustachian tube, tympanum and utriculus
D) perilymph, ear ossicles and semicircular canals.

Answer 1

Hint: Ears are the sensory organs that detect and receive the sound waves and convert them into the nerve impulses, hence help in hearing. However, hearing isn't the only function of the ears.
Complete answer:
The structure of the human ear: Anatomically, the ear is often divided into three major sections called
(a) The external ear: The external ear consists of the pinna and external acoustic meatus that results in a canal. Pinna may be a flap of elastic cartilage, visible from the outside. Pinna is just a sound-gathering trumpet. The sound waves or the sound vibrations need a medium to travel and this medium is provided by the air. The pinna collects these sound waves travelling within the air. Next comes the external acoustic meatus and canal. (Auditory term comes within the relation of the sound). The canal carries the sound waves, that's why it's called the external auditory meatus. The sound waves, present within the air, are collected by the pinna and carried inwards by the external auditory meatus. There are very fine' (small) hairs and wax secretory sebaceous (oil) glands within the skin of the pinna and therefore the meatus. The wax secreting sebaceous glands produce an oily secretion called the ear wax.
 

 (b) The tympanic cavity: the centre ear contains three delicate bones, called the ear ossicles. The three ear ossicles are the malleus, incus and stapes. The malleus bone is hammer-shaped. Out of the three ear ossicles, malleus is that of the outer one. The handle of malleus is attached to the inner side of the eardrum. Incus bone lies within the middle of three ear ossicles and is attached to malleus on the outer side and to stapes on the inner side. The incus bone is anvil-shaped (anvil is an instrument, commonly employed by cobblers). The third in the line of this chain of bones is the tapes which are stirrup-shaped.
(c) the internal ear: The internal ear is termed because of the labyrinth. The fluid that occurs inside the internal ear is called lymph, which is of two types, the perilymph and therefore the endolymph. The labyrinth itself consists of two parts, the osseous labyrinth and therefore the structure. The osseous labyrinth, as the name depicts, is a series of channels made from the bony part. Inside the osseous labyrinth, lies the structure.
Hence, the correct answer is option A.

Note: Ears are sensory organs of the body. In addition to auditory functions, it also maintains the body balance or body equilibrium. So, ears perform two sensory functions: hearing, and maintenance of body balance.