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
The couinaud's segmental nomenclature is based on the position of the - 
Select and explain. 
A. Hepatic veins and portal vein, B. Hepatic veins and bilary ducts, C. Portal vein and bilary ducts, D. Portal vein and hepatic artery
A: Hepatic veins and portal vein
Answer: A: Hepatic veins and portal vein 
Explanation: Based on the distribution of the portal vein and hepatic vein, couinaud divided functional lobes of liver into eight segments.