This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anesthesia, Subject name: Pharmacology
Central muscle relaxants act by 
Select and explain. 
A. Decreasing muscle excitation, B. Decreasing spinal polysynaptic reflexes, C. Inhibiting spinal polysynaptic reflexes, D. Decreasing nerve conduction
C: Inhibiting spinal polysynaptic reflexes
Answer: C: Inhibiting spinal polysynaptic reflexes 
Explanation: Refer KDT 6/e p 348 Centrally acting muscle relaxants reduce skeletal muscle tone by a selective action in the cerebrospinal axis, without altering consciousness They selectively depress spinal and supraspinal polysynaptic reflexes Polysynaptic pathways in the ascending reticular formation which are involved in the maintenance of wakefullness