Which condition is characterized by a barking cough and stridor?

The condition characterized by a barking cough and stridor is croup. Croup is primarily caused by viral infections, especially in young children, leading to inflammation and narrowing of the upper airway. The hallmark symptoms of croup are the distinctive, seal-like barking cough and stridor, which occurs during inspiration due to the obstruction of airflow through the larynx. These symptoms arise from swelling in the respiratory tract, particularly around the vocal cords, which is common in croup cases.

In contrast, bronchitis typically presents with a persistent cough that may produce mucus but does not usually have the barking sound associated with croup. Pneumonia is characterized by symptoms such as a productive cough, fever, chest pain, and difficulty breathing rather than the specific barking cough and stridor. Asthma can cause wheezing and shortness of breath but does not typically result in a barking cough or stridor. Therefore, the symptoms seen in croup distinctly set it apart as the correct answer.