A Small Amount of Fluid Is Contained in the Pleural

A small amount of fluid is contained in the pleural cavity to

A) promote the exchange of nutrients with both lungs.
B) allow gas exchange between the lungs and the blood stream.
C) allow white blood cells and macrophages access to foreign antigens entering the body through air.
D) function as a lubricant as the lungs move during ventilation.
E) serve as a shock absorber for the lungs during body movement.