This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
[{'content': 'The pacemaker of intestine is: \nSelect and explain. \nA. Interstitial cells of cajal, B. Smooth muscle, C. Collagen fiber, D. All', 'role': 'user'}, {'content': 'Answer: A \nExplanation: The pacemaker of intestine is Interstitial cells of cajal. They in association with smooth muscle cells act as pacemakers Ref:Guyton and Hall textbook of medical physiology 12th edition,page number:395,396', 'role': 'assistant'}]