This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology, Subject name: Medicine
Maximum amount of alkaline phosphatase is seen in: 
Select and explain. 
A. Semen, B. Placenta, C. CSF, D. Plasma
A: Semen
Answer: A: Semen 
Explanation: Ans: a