Which statement best describes cystic fibrosis?
◦ Obstructive airway disease characterized by reversible airflow obstruction, bronchial hyperreactivity, and inflammation
◦ Respiratory disease characterized by severe hypoxemia, decreased pulmonary compliance, and diffuse densities on chest x-ray imaging
◦ Pulmonary disorder involving an abnormal expression of a protein-producing viscous mucus that obstructs the airways, pancreas, sweat ducts, and vas deferens
◦ Pulmonary disorder characterized by atelectasis and increased pulmonary resistance as a result of a surfactant deficiency