Which description would the nurse provide the parents of an infant who are asking about what a patent ductus arteriosus (PDA) is ________.
1) The diameter of the aorta is enlarged.
2) The wall between the right and left ventricles is open.
3) It is a narrowing of the entrance to the pulmonary artery.
4) It is a connection between the pulmonary artery and the aorta.