What sound might indicate an upper airway obstruction in a patient?

Crowing, also known as stridor, is a high-pitched sound heard during inspiration and indicates upper airway obstruction, often caused by swelling, foreign body, or infection such as croup or epiglottitis.

Option D is correct.

Option A (Rhonchi) and B (Wheezing) are lower airway sounds.

Option C (Bubbling) suggests fluid in the airway, not obstruction.

NREMT emphasizes rapid recognition of stridor because upper airway obstruction can quickly become fatal.