This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Respiratory rhythm generation center is located at: 
Select and explain. 
A. Dorsal respiratory group, B. Pre-Botzinger complex, C. Ventral respiratory neurons, D. Pneumotaxic center
B: Pre-Botzinger complex
Answer: B: Pre-Botzinger complex 
Explanation: Ans: B. Pre-Botzinger complexRef: Ganong 25Ie p656, 24Ie p658)Rhythmic respiration is initiated by a small group of synaptically coupled pacemaker cells in the pre-Botzinger complex (pre-BOTC) on either side of the medulla between the nucleus ambiguus and the lateral reticular nucleus.The main components of the respiratory control pattern generator responsible for automatic respiration are located in the medulla. Rhythmic respiration is initiated by a small group of synaptically coupled pacemaker cells in the pre-Botzinger complex (pre-BOTC) on either side of the medulla between the nucleus ambiguus and the lateral reticular nucleus.