What condition does the term "bronchospasm" refer to?

Bronchospasm refers specifically to the constriction of the airways, which occurs when the muscles surrounding the bronchial tubes tighten. This tightening narrows the air passages, making it difficult for air to flow into and out of the lungs. Bronchospasm is commonly associated with conditions such as asthma, chronic obstructive pulmonary disease (COPD), and allergic reactions, where the response of the airways to various stimuli can lead to breathing difficulties.

In contrast, other options describe different respiratory conditions: inflammation of lung tissue relates to pneumonia or interstitial lung disease; fluid accumulation in the lungs refers to conditions like pulmonary edema; and infection within the bronchial tubes pertains to bronchitis. Each of these reflects a distinct pathology, while bronchospasm specifically addresses the physical constriction of airways, leading to restricted airflow.