Final answer:
Stridor occurs in croup, epiglottitis, and foreign body aspiration. Hence the correct answer is option A
Step-by-step explanation:
Stridor is a high-pitched, wheezing sound that occurs during breathing and is typically caused by a blockage or narrowing of the upper airway. Stridor is commonly associated with croup, which is a viral infection that causes inflammation of the larynx and trachea. Other conditions that can cause stridor include epiglottitis, which is a bacterial infection that causes inflammation of the epiglottis, and foreign body aspiration, where an object becomes lodged in the airway.
Hence the correct answer is option A