Final answer:
The nurse would classify the 79-year-old with a temperature of 104°F (40°C) as urgent due to the potential severity of the situation.
Step-by-step explanation:
In the context of triaging patients in the emergency department, the nurse would classify the 79-year-old with a temperature of 104°F (40°C) as urgent.
A high fever like this indicates a potentially serious infection or underlying health issue, especially in an elderly person.
It is important for the nurse to prioritize the assessment and treatment of this patient to prevent further complications.