Final answer:
The pleural fluid helps to prevent disease and damage from nearby lobes and keep it from spreading.
Step-by-step explanation:
The primary topic of this question is the respiratory system.
The pleural fluid helps to prevent disease and damage from nearby lobes and keep it from spreading. It acts as a lubricant between the layers of the pleura, preventing friction between them and potential damage.
Therefore, the correct answer is: C. Pleural fluid.
The fluid that lines the pleura prevents diseases or infections from spreading. It has antibodies and immune cells that can aid in the fight against infections and stop them from spreading to other parts of the body or lung. The pleural fluid contributes to the protection of the adjacent lobes and the prevention of disease transmission by isolating and containing potential pathogens.