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
Ligamentum teres hepatis is derivative of: 
Select and explain. 
A. Ductus aeriosus, B. Ductus venosus, C. Umbilical vein, D. None of the above
C: Umbilical vein
Answer: C: Umbilical vein 
Explanation: After bih, the left umbilical vein and ductus venosus are obliterated and form the ligamentum teres hepatis and ligamentum venosum, respectively. Ref: Langman's embryology 11th edition Chapter 12.