Answer the following question given this paragraph: 

Pneumonia is a disease in which some of the alveoli of the lungs fill with fluid so gas exchange cannot occur. Symptoms usually include coughing, chest pain, and difficulty breathing. Pneumonia may be caused by an infection or injury of the lungs.


Q: What is the disease where some alveoli of the lungs fill with fluid?

 Choices:

- leukemia

- lung cancer

- lyme disease

- pneumonia

A:
pneumonia
