This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Development of GU system and Neuro-vascular supply of pelvis & perineum, Subject name: Anatomy
The nerve mediating pain of External hemorrhoids is: 
Select and explain. 
A. Hypogastric nerve, B. Inferior rectal nerve, C. Pelvic splanchnic nerve, D. Sympathetic plexus
B: Inferior rectal nerve
Answer: B: Inferior rectal nerve 
Explanation: -External hemorrhoids --> present below pectinate line , painful bleeding is present --> pain carried by Inferior Rectal Nerve (branch of pudendal nerve). -Internal haemorrhoids --> present above pectinate line --> painless bleeding is its feature.