I'm looking to have the Master Audio game object persist through only certain scenes but not all of them. I guess what I'm trying to do is have one track in a World Selector scene. Then, after a world is selected, another track would play through multiple scenes within that world with no break in the music. When the world is completed, the music should change to the original music when going back the World selector scene. Is this possible?
So you probably do want to use a persistent Master Audio so it will be seamless. You can trigger whichever other music you like in the other scenes, which you can set up either in Dynamic Sound Group Creators or the main Master Audio game object playlist. Then when you return to the main scene, you can have a game object in that scene play the original music track again, using Event Sounds script.