This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Physiology
[{'content': 'The cyclical flexion and extension motions of a leg during walking result from activity at which level of the nervous system? \nSelect and explain. \nA. Cerebral coex, B. Cerebellum, C. Globus pallidus, D. Spinal cord', 'role': 'user'}, {'content': 'Answer: D \nExplanation: The spinal cord has the intrinsic circuitry in the form of central paftern generators to produce the basic motions of walking.', 'role': 'assistant'}]