Final answer:
The characteristic of an infant cough due to an upper respiratory tract infection is a 2) wet cough.
Step-by-step explanation:
When an infant has an upper respiratory tract infection, such as a common cold or bronchiolitis, they may have a wet cough accompanied by phlegm or mucus. This is because the infection irritates the airways, causing increased mucus production and congestion.
For example, a common viral infection that can cause a wet cough in infants is respiratory syncytial virus (RSV). RSV is a common cause of respiratory tract infections in young children and can lead to symptoms such as coughing, wheezing, and difficulty breathing.
It's important to note that wet coughs are not exclusive to upper respiratory tract infections and can also be present in lower respiratory tract infections such as pneumonia. In these cases, the wet cough may be accompanied by other symptoms like fever, chest pain, and rapid breathing. The correct answer is 2) wet cough