This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General anatomy, Subject name: Anatomy
What is the embryolgical remnant of median umbilical ligament? 
Select and explain. 
A. Urachus, B. Allantois, C. Amnion, D. Yolk sac
A: Urachus
Answer: A: Urachus 
Explanation: Median umbilical ligament is a remnant of urachus If patent urachus in adults, urine dribbles from umbilicus known as wheeping umbilicus