Final answer:
The most appropriate action for the nurse to take is to apply pressure to the area for at least 15 minutes. Applying pressure helps promote the formation of a blood clot and control bleeding.
Step-by-step explanation:
The most appropriate action for the nurse to take in this situation is to apply pressure to the area for at least 15 minutes. Applying pressure helps to promote the formation of a blood clot, which is the first step in the body's wound-healing response. For a child with hemophilia, it is important to control bleeding as much as possible to minimize the risk of further complications.