An 8-Month Old Boy Is Presented to the Pediatric Emergency

An 8-month old boy is presented to the pediatric emergency department due to breathlessness. In the last previous days, the patient had a runny stuffy nose. She started coughing this evening with breathing noises. The patient has met all his developmental stages and received all of her immunizations. The patient has a barking cough, inspiratory stridor, and intercostal retractions. Which part of the airway is the most likely affected in this patient?

A) A
B) B
C) C
D) D
E) E
F) F