Upper Respiratory Infection most directly involves which part of the airway?

• A. Bronchi
• B. Lungs
• C. Nose
• D. Alveoli

Answer: (C)

The main idea here is that upper respiratory infections target the upper part of the airway—the nose and its surrounding mucosa. Infections like the classic cold typically start in the nasal passages, causing congestion, runny nose, and sneezing because the nasal mucosa is the first encounter for many viruses.

The other structures listed belong to the lower respiratory tract. The bronchi conduct air deeper into the lungs, and the alveoli are the sites of gas exchange. Infections in those areas are lower respiratory infections (like bronchitis or pneumonia) and are not the direct focus of an upper respiratory infection. So the nose is the part most directly involved in URIs.