This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Acyanotic congenital hea diseases, Subject name: Pediatrics
True statement about ductus aeriosus is: 
Select and explain. 
A. It undergoes anatomic closure within 24 hours of bih, B. It connects aoa with pulmonary vein, C. It is induced to close by high levels of prostaglandins, D. May cause a machinery murmur by its patency
D: May cause a machinery murmur by its patency
Answer: D: May cause a machinery murmur by its patency 
Explanation: IMPOANT POINTS ABOUT DUCTUS AERIOSUS: - Physiological closure: occurs almost immediately after bih by contraction of muscular wall - Anatomic closure: occurs by proliferation of intima in 10-21 days after bih - After obliteration, it forms ligamentum aeriosum. - Murmur due to PDA - Continuous machinery murmur. - Ductus aeriosus is kept open with the help of prostaglandins in ductus dependent conditions Note : Prostaglandin inhibitors are used to close the ductus aeriosus. Intravenous (IV) indomethacin or ibuprofen is used to treat patent ductus aeriosus (PDA) in premature infants.