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
[{'content': 'Foramen ovale closes because of fusion of - \nSelect and explain. \nA. Septum primum + Endocardial cushion, B. Septum secundum + Endocardial cushion, C. Septum primum + Septum secundum, D. None', 'role': 'user'}, {'content': 'Answer: C \nExplanation: None', 'role': 'assistant'}]