The correct answer is: D. causes fluids to leak into the alveoli.
Pneumonia is an inflammatory condition of the lungs that is usually caused by infection with viruses or bacteria. Pneumonia causes the fluid fill of the alveoli (air sacs). As a result symptoms such as cough with phlegm or pus, fever, chills, and difficulty breathing might occur. Pneumonia can be serious condition, especially for infants and people with weakened immune systems.