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
During embryological development, all of the following organs develop in the peritoneal cavity suspended on a mesentery, EXCEPT ? 
Select and explain. 
A. Liver, B. Spleen, C. Kidney, D. Pancreas
C: Kidney
Answer: C: Kidney 
Explanation: Kidney is a retro-peritoneal organ.During development, some organs develop in the peritoneal cavity suspended on a mesentery called as intraperitoneal organs. They include,StomachFirst pa of duodenumJejunumIleumTransverse colonSigmoid colonLiver SpleenSome abdominal organs develop behind the peritoneum and are called retro-peritoneal organs. They are,KidneysUretersSuprarenal glandsRectumRef: Grant's Dissector By Patrick W. Tank, John Charles Boileau Grant, 2012, Page 99.