The Carotid Bodies Contain ________ Chemoreceptors That Respond to Changes

The carotid bodies contain ________ chemoreceptors that respond to changes in ________.

A) peripheral; blood concentrations of H⁺ and O₂
B) central; blood concentrations of H⁺, but not CO₂ and O₂
C) peripheral; cerebrospinal fluid concentrations of H⁺
D) central; cerebrospinal concentrations of CO₂
E) peripheral; concentrations of carbon, dust, and pollution in the lungs