Answer:
The presence of air in the pleural cavity
Explanation:
A pneumothorax occurs when air builds up between the lung and the chest wall. In consequence, pneumothorax occurs when air gets into the pleural cavity (i.e., the space between the lung and the chest wall) and causes a fully and/or partially collapsed lung. Some of the most common symptoms of pneumothorax include shortness of breath (respiratory distress), rapid breathing, rapid heart rate, fatigue, agitation, dry cough, etc. Pneumothorax can be caused by a chest injury, an accident during a medical procedure, damage from underlying lung diseases, etc.
The answer to the question is B
