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: Gynaecology & Obstetrics
Heat stable alkaline phosphatase In pregnancy is derived from : 
Select and explain. 
A. Placenta, B. Maternal liver, C. Fetal liver, D. All of the above
A: Placenta
Answer: A: Placenta 
Explanation: Placenta