What happens to intrathoracic pressure in a simple pneumothorax?
A) Intrathoracic pressure decreases due to the escape of air into the pleural space.
B) Intrathoracic pressure increases, causing compression of the affected lung.
C) There is no change in intrathoracic pressure in a simple pneumothorax.
D) Intrathoracic pressure fluctuates but remains within the normal range.