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: Surgery
Which of the following is the most troublesome source of bleeding during a radical retropubic prostatectomy? 
Select and explain. 
A. Dorsal venous complex, B. Inferior vesical pedicle, C. Superior vesical pedicle, D. Seminal vesicular aery
A: Dorsal venous complex
Answer: A: Dorsal venous complex 
Explanation: Main source of potential bleeding during prostatectomy is the dorsal vein complex that passes over the prostate gland. Ref: Prostate Cancer: Science and Clinical Practice By Jack H. Mydlo, Ciril J. Godec, 2003, Page 281; Joan and Sanford I Weill. C. Cornell Urology- Review Aicle 'Prostatectomy'