This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Hepatobiliary System, Subject name: Anatomy
Boundaries of foramen of Winslow are all EXCEPT: 
Select and explain. 
A. Caudate lobe of liver, B. Inferior vena cava, C. Free border of lesser omentum, D. 4th part of Duodenum
D: 4th part of Duodenum
Answer: D: 4th part of Duodenum 
Explanation: ANSWER: (D) 4th part of DuodenumREF: Gray s anatomy 39th edition, page 3136 Repeat from June 2009 and June 2011In human anatomy, the omental foramen (Epiploic foramen, foramen of Winslow, or uncommonly aditus) is the passage of communication, or foramen, between the greater sac (general cavity of the abdomen), and the lesser sac.Borders of Epiploic foramen:It has the following borders:Anterior: the free border of the lesser omentum, known as the hepatoduodenal ligament. This has two layers and within these layers are the common bile duct, hepatic artery, and hepatic portal vein.Posterior: the peritoneum covering the inferior vena cavaSuperior: the peritoneum covering the caudate lobe of the liverInferior: the peritoneum covering the commencement of the duodenum and the hepatic artery, the latter passing forward below the foramen before ascending between the two layers of the lesser omentum.Left lateral: Gastrosplenic ligament and Splenorenal ligament.