Question

what is a pneumothorax?
multiple choice
abnormal constriction of the upper airways
loss of alveolar walls
infection within the lung
air within the pleural space

Explanation:

A pneumothorax is defined as air within the pleural space. Abnormal constriction of the upper airways is more related to conditions like croup. Loss of alveolar walls is characteristic of emphysema. Infection within the lung is typical for pneumonia.

Answer:

Air within the pleural space