Which of the following senses is most closely related to balance?
a. touch
b. smell
c. hearing
d. taste

C. Hearing

Ears are also responsible for balance, in the part of the Cochlea.

Here you will find a liquid-filled cavity that functions to maintain balance and movement.

Whenever a sound reaches the ear, it creates a sound wave that creates vibration in the eardrum. The pressure when high pushes the membrane inwards while low pressure sound waves helps the eardrum to come outwards.  

These sound waves are then transduced when it reaches the cochlea where hair-like structures interprets the sensory information and is relayed to the brain.