Final answer:
The nurse checks the catheter for intactness after removal to ensure no part of it has broken off inside the patient's vein, which could lead to complications.
Step-by-step explanation:
The correct response by the nurse when looking at a discontinued peripheral IV catheter is "D. inspecting the catheter for intactness." Ensuring the catheter is intact is a critical step in the process, as a missing catheter tip could indicate that a piece has broken off and may have been left inside the patient's vein, which could lead to serious complications. Checking for clot formation on the tip or exudate is also vital, as these could be signs of infection or phlebitis, which would require immediate attention. Noting the gauge of the catheter is part of proper documentation, but the primary concern is patient safety through ensuring the catheter's intactness after removal.