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
Foramen ovale closes because of fusion of 
Select and explain. 
A. Septum primerm + Endocardial cushion, B. Septam serunsum + Endocardial cushion, C. Septum primerm + Septam serunsum, D. None
C: Septum primerm + Septam serunsum
Answer: C: Septum primerm + Septam serunsum 
Explanation: The septum primerm and septum secundum press againest each other close the communication (forman ovale) between the two arteria, complited at around 3 months after birth.