Answer:
Semicircular canals
Explanation:
Ear is one of the important sense organ responsible for hearing and equilibrium. Human ear is divided into three parts: outer ear, middle ear and inner ear.
Inner ear is mainly responsible for the equilibrium of the body. Vestibular apparatus together with semicircular canals is responsible for the dynamic equilibrium of the body. Dynamic equilibrium involves head rotation and vertical movements of the body.
Thus, the correct answer is option (a).
Coal
Coal is a combustible black rock that is formed from prehistoric plant remains. Coal is formed from the anaerobic decomposition of dead plant matter such as trees, ferns, mosses and other marsh plants that grew on the earth surface over millions of years ago. Coal is composed largely of carbon and is usually burned as a fuel.
Soil is a mixture of weathered rock and organic material.
Multicellular
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