What is a wheeze primarily characterized by?

A wheeze is primarily characterized by a whistling or sighing sound that occurs during breathing, particularly when exhaling. This sound is produced by the narrowing or obstruction of the airways, which leads to turbulent airflow. Wheezing is commonly associated with conditions such as asthma or bronchitis, where inflammation or constriction of the air passages creates the distinct sound.

The other options, while related to respiratory conditions, do not accurately describe the specific characteristic of wheezing. A strong cough reflex may accompany respiratory issues but does not define wheezing itself. Persistent chest pain can indicate serious respiratory or cardiac concerns but is not related to the sound associated with wheezing. An increased respiratory rate may occur in response to respiratory distress but does not specifically identify the auditory characteristic of a wheeze. Therefore, the defining feature of a wheeze is indeed the whistling or sighing sound it produces.