This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Physiology
CO2 increases ventilation by acting mainly on receptors of 
Select and explain. 
A. Apneustic center, B. Pneumotaxic center, C. Vental surface of medulla, D. DRG
C: Vental surface of medulla
Answer: C: Vental surface of medulla 
Explanation: In the medulla, the ventral respiratory group (VRG) consists of four groups of neurons that make up the exhalation (expiratory) area of respiratory control. ... The VRG contains both inspiratory and expiratory neurons. In quiet, restful breathing, the ventral respiratory group of neurons are inactive Ref: guyton and hall textbook of medical physiology 12 edition page number: 370,371,372