Emergency Medical Technician (EMT) Practice Test 2025 – All-in-One Guide to Exam Success!

Pneumonia is defined as an infection that causes inflammation in the alveoli, which are the tiny air sacs in the lungs where gas exchange occurs. When these alveoli become infected, they can fill with fluid or pus, leading to symptoms such as coughing, fever, chills, and difficulty breathing. The infection can be caused by various microorganisms, including bacteria, viruses, or fungi.

Answering with the option that describes pneumonia as an infection of the alveoli accurately captures the primary location and mechanism of the disease. The other options describe other respiratory conditions: inflammation of the airways refers to conditions like bronchitis; an infection of the bronchi specifically addresses bronchial infections; and an infection of the pleural cavity pertains to pleuritis or empyema, which is not pneumonia. Each of these conditions affects different structures in the respiratory system, making it crucial to understand the distinction between them.