The correct option is C Calcium carbonates
Otoconia are small crystals of calcium carbonate in the saccule and utricle of the ear which under the influence of acceleration in a straight line cause stimulation of the hair cells. Otoliths are commonly referred to as "earstones" or "fish ear bones". They are hard, calcium carbonate structures located directly behind the brain of teleost (bony) fish. Otoliths help with balance, orientation, and sound detection.