Final answer:
Surfactant increases lung compliance (option A) and reduces surface tension in the alveoli, making it easier to inflate the lungs and facilitating gas exchange. It is crucial for preventing respiratory distress in premature infants.
Step-by-step explanation:
The purpose of surfactant in the lungs is primarily to increase lung compliance. Surfactant functions like a detergent by reducing the surface tension within the alveoli, which decreases the effort required to inflate the lungs. This is particularly important in the neonatal period, as infants born prematurely may lack sufficient surfactant, leading to respiratory distress syndrome. Surfactant also plays a vital role in maintaining the stability of alveoli by preventing their collapse, thereby facilitating efficient gas exchange.