Which characteristic of stridor is notable?

Stridor is a high-pitched, wheezing sound that is typically heard during inhalation and is associated with turbulent airflow through a narrowed or obstructed upper airway. The notable characteristic is that it indicates an issue in the upper airway, often due to conditions like laryngomalacia, croup, or foreign body aspiration. This sound arises specifically from the narrowing at levels such as the larynx or trachea, making it a critical sign in clinical assessment.

The other options do not align with the defining characteristics of stridor. For instance, stridor is not primarily associated with the lower airway or lung congestion, which would be more indicative of conditions like wheezing. Additionally, while stridor may occur alongside fever in some infections, it is not a definitive symptom and is not always present. Therefore, the correct understanding of stridor's significance relates back to its indication of upper airway obstruction or narrowing.