What symptom is least likely to be associated with an upper respiratory infection?

Severe abdominal pain is the symptom least likely to be associated with an upper respiratory infection. Upper respiratory infections, such as the common cold or viral pharyngitis, typically present with symptoms affecting the nasal passages and throat, which include cough, sore throat, and sometimes myalgia. Myalgia, or muscle aches, can occur due to general malaise and systemic effects of a viral infection. However, abdominal pain is not a common symptom of upper respiratory conditions; it is more often related to gastrointestinal issues or infections. Thus, when considering the symptom profile of upper respiratory infections, severe abdominal pain stands out as the least relevant.