A nurse is caring for an 8-month-old infant who is receiving intravenous (IV) fluids via a 24-gauge catheter. Which of the following statements by the client's mother indicates that the nurse should check the site for signs of infiltration?

A. "My baby's fingers are looking swollen.": Swelling around the IV site can indicate infiltration, where IV fluids leak into surrounding tissues rather than being infused into the vein. B. "The tape is coming off the IV needle.": While loose tape may need to be replaced, it does not specifically indicate infiltration. C. "There's blood backing up my baby's IV tubing.": Blood backflow can indicate various issues such as improper placement or the IV being too low, but not necessarily infiltration. D. "There's a long red streak up my baby's arm.": A red streak can indicate phlebitis, inflammation of the vein, rather than infiltration, which typically presents with swelling and coolness around the IV site.