Final answer:
Administering oxygen 4 L/min per nasal cannula is a physician-initiated intervention.
Step-by-step explanation:
A physician-initiated intervention is an action or treatment that a physician initiates without a specific order from another healthcare professional. In the given options, administering oxygen 4 L/min per nasal cannula is a physician-initiated intervention. This is because it is the physician's decision to administer oxygen to the patient based on their assessment of the patient's condition and need for oxygen therapy.