Final answer:
The action that demonstrates nurse autonomy is when the nurse checks the policy manual before changing the central line dressing.
Step-by-step explanation:
The action that demonstrates the concept of nurse autonomy is d. The nurse checks the policy manual before changing the central line dressing. Nurse autonomy refers to the nurse's ability to make independent decisions and take responsibility for their actions within the scope of their practice. By checking the policy manual, the nurse is ensuring that they are following the proper protocols and guidelines for changing the central line dressing, showing autonomy in their decision-making process.