Which of the following is a common symptom of strep throat?

A common symptom of strep throat is the presence of white patches on the tonsils. This symptom occurs due to the bacterial infection caused by Streptococcus pyogenes, which often leads to the formation of these patches or spots, indicating pus formation and inflammation in the throat. When examining a patient with strep throat, a healthcare provider may visualize these white patches during a throat examination.

In contrast, a dry cough is more commonly associated with viral infections and is not a specific indicator of strep throat. Similarly, a runny nose is typically linked to upper respiratory infections like the common cold rather than strep throat. Ear pain can occur but is usually a secondary symptom resulting from referred pain due to throat inflammation rather than a primary symptom of the condition. Thus, the presence of white patches on the tonsils is a definitive symptom pointing to a diagnosis of strep throat.