The major chemoreceptor sites responsive to changes in PaCO2 are located in the:
(A) Carotid body.
(B) Aortic body.
(C) Brainstem.
(D) Carotid sinus.
(E) Cerebral cortex

The central chemoreceptors controlling ventilation respond to the:
(A) Hydrogen ion activity of arterial blood.
(B) Hydrogen ion activity of jugular venous blood.
(C) PO2 of cerebrospinal fluid.
(D) PO2 of arterial blood.
(E) Hydrogen ion activity of cerebrospinal fluid.

Discussion encourage. Open for any of y'all to answer!!