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
Lowest most level of integration of stretch reflex is at 
Select and explain. 
A. Cerebral cortex, B. Lower Medulla, C. Spinal cord, D. All of the above
C: Spinal cord
Answer: C: Spinal cord 
Explanation: None