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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following events cause closure of ductus arteriosus in new born
assistant
The correct answer is  Aeration of newborn lung causes rapid replacement of bronchial and alveolar fluid by air, with this compression of pulmonary vasculature is lowered which results in fall in pulmonary arterial blood pressure.
Thus ductus arteriosus closes.