What is the definition of persistent pulmonary hypertension (PPH)?

It is characterized by an alteration in the transition from fetal to neonatal circulation.
It is a respiratory difficulty characterized mainly by tachypnea, usually of short, benign, and self-limited course.
It is a condition characterized by a change in the passage of fetal circulation to neonatal circulation.
It is a condition characterized by high pressure in the pulmonary artery and pulmonary vascular resistance, leading to pulmonary hypoperfusion and right-to-left shunts through the ductus and foramen ovale.