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: Anatomy
Watershed line in anal canal ? 
Select and explain. 
A. Hilton's line, B. Pectinate line, C. Mucocutaneous junction, D. None
B: Pectinate line
Answer: B: Pectinate line 
Explanation: Ans. is 'b' i.e., Pectinate linePectinate line forms the water-shed line of anal canal.Area above pectinate line drains into internal iliac nodes and area below it drains into superficial inguinal nodes.