The position of the head with respect to gravity is determined by the .a. shift in fluid in the semicircular canals. b. movements of otoliths in response to gravity. c. movements of perilymph in the vestibular chamber. d. impulses transmitted from the macula of the semicircular canals. e. stimulation of the cochlear portion of the nerve.

B) movements of otoliths in response to gravity.

Explanation:

The anatomy of the inner ear shows that the inner ear contains the vestibule and the semicircular canals. The vestibule contains the saccule and the utricle and these together make the otolith organs.

The semicircular canals contain the fluid and help maintain the equilibrium of the posture whereas the vestibule contains the otolith organs which help determine the position of the head in respect to the gravity of the Earth.

Thus, Option-B is the correct answer.