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: Pharmacology
A newborn was diagnosed as having a congenital abnormality that resulted in transposition of great vessels. While preparing the infant for surgery, the medical team needed to keep the ductus arteriosus open. They did this by infusing : 
Select and explain. 
A. Cortisol, B. Indomethacin, C. Alprostadil, D. Tacrolimus
C: Alprostadil
Answer: C: Alprostadil 
Explanation: None