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: Anaesthesia
Site of action of epidural analgesia – 
Select and explain. 
A. Sensory nerve ending, B. Ventral horn, C. Substantia gelatinosa, D. Cortex
C: Substantia gelatinosa
Answer: C: Substantia gelatinosa 
Explanation: Epidural opioid analgesics → act on opioid receptors present in substantia gelatinosa of dorsal horn cells.
Epidural local anesthetics → act on nerve roots.