This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Peritoneum, Subject name: Surgery
Ormond's disease is: 
Select and explain. 
A. Idiopathic lymphadenopathy, B. Retractile testis, C. Idiopathic retroperitoneal fibrosis, D. Idiopathic mediastinitis
C: Idiopathic retroperitoneal fibrosis
Answer: C: Idiopathic retroperitoneal fibrosis 
Explanation: Ans: c (Idiopathic retroperitoneal fibrosis)Ref: Bailey & Love, 24th ed, p. 1151, T 67.16 & 23rd ed, p. 1024, T 56.9