This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Physiology
Pacemaker is formed by which of the following cells in GIT? 
Select and explain. 
A. P- cells, B. Oxyntic cells, C. Cajal cells, D. Parietal cells
C: Cajal cells
Answer: C: Cajal cells 
Explanation: Interstitial cells of Cajal are the Stellate Mesenchymal pacemaker cells Ref: Ganong 25th ed/page 496