52. The breathing in human is controlled by all of the following mechanisms EXCEPT
(A) The sensors in the walls of the aorta and carotid arteries in the neck detect changes in blood pH and send nerveimpulses to the medulla.
(B) The sensors in the aorta and carotid arteries also detect changes in 0 2 levels in the blood and signal the medulla toincrease the breathing rate.
(C) Nerves from a breathing control center in the medulla oblongata of the brain send impulses to the diaphragm and ribmuscles, stimulating them to contract and causing inhalation.
(D) Sensors in the medulla detect changes in the pH of the blood and interistial fluid bathing the surface of the brain.
(E) The control center in the medulla sets the basic rhythm, and a control center in the pons moderates it, smoothing outthe transitions between inhalations and exhalations.