After CPR has been started, when would it be appropriate to stop? When the scene becomes unsafe for the rescuer

When an equally trained or more advanced trained rescuer takes over for you

When the victim begins to move and breathe normally

All of the above

All of the above.

Explanation: Obviously if the scene becomes unsafe in some way you would want to be out of there if it meant saving your own life over theirs. If someone equally trained or someone with advanced knowledge takes over then they can better help that person. And if the victim begins to move and breathe normally they can breathe on their own no need for CPR. Hope this helps!