The Perinatal Nurse Explains the Cardiopulmonary Adaptations That Occur in the Neonate

The perinatal nurse explains the cardiopulmonary adaptations that occur in the neonate to a student nurse.Which of the following statements accurately describes the sequence of these changes?

A) "As air enters the lungs,the PO2 rises in the alveoli,which causes pulmonary artery relaxation and results in an increase in pulmonary vascular resistance."
B) "As the pulmonary vascular resistance increases,pulmonary blood flow increases,reaching 100% by the first 24 hours of life."
C) "Decreased pulmonary blood volume contributes to the conversion from fetal to newborn circulation."
D) "Once the pulmonary circulation has been functionally established,blood is distributed throughout the lungs."