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
The cyclical flexion and extension motions of a leg during walking result from activity at which level of the nervous system? 
Select and explain. 
A. Cerebral coex, B. Cerebellum, C. Globus pallidus, D. Spinal cord
D: Spinal cord
Answer: D: Spinal cord 
Explanation: The spinal cord has the intrinsic circuitry in the form of central paftern generators to produce the basic motions of walking.