In a patient with bronchitis, which of the following is a common symptom?

A persistent dry cough is a hallmark symptom of bronchitis, especially in cases of acute bronchitis. In this condition, the inflammation of the bronchial tubes leads to increased mucus production and irritation, which manifests primarily as a cough. The cough may start as dry but often progresses to a productive cough with sputum, particularly in cases of acute bronchitis.

While other symptoms like chest pain, fever and chills, or shortness of breath on exertion can be associated with bronchitis, they are not as defining as the persistent cough. Chest pain may occur due to coughing or muscle strain, but it is not a primary symptom of bronchitis itself. Fever and chills can indicate an infection, but they are more commonly seen in cases of bacterial bronchitis or other respiratory infections rather than as common symptoms of bronchitis. Shortness of breath on exertion can also occur, especially in chronic bronchitis, but it isn't as immediately indicative as a persistent dry cough. Therefore, the persistent dry cough stands out as a key characteristic symptom of bronchitis.