Final answer:
A child with a barking cough, hoarseness, and respiratory distress likely has croup, which is characterized by infection and swelling in the upper airway.
Step-by-step explanation:
A child presenting with a barking cough, hoarseness, and respiratory distress is most likely suffering from croup. Croup is an infection of the upper airway, which obstructs breathing and causes a characteristic barking cough and hoarseness due to swelling around the vocal cords. In contrast, conditions like pneumonia involve inflammation of the alveoli and fluid accumulation, asthma involves chronic inflammation leading to narrowed airways, and bronchiolitis is a viral infection affecting the small airways in infants. If the child has respiratory symptoms such as shortness of breath, wheezes or stridor, and pain with swallowing in addition to cough and hoarseness, these factors underline the diagnosis of croup.