A 22 year old G2 P1 presents with rupture of membranes at 19 weeks. She subsequently delivers. Which of the following is seen in autopsy of lungs of nonviable fetus: (A) No cartilage development, (B) Terminal sacs present, (C) Normal bronchial branching, (D) Mature alveoli
Answer is C. Lung maturation stages:

Pseudo glandular stage  : growth of intersegmental bronchial tree.
Canalicular stage  : Bronchial cartilage plates extend peripherally.
Terminal sac stage  : Respiratory bronchioles gives rise to terminal sacs.
Alveolar stage  : alveolar epithelial lining thins to improve gas exhange.