This sound comes from Undertale, the indie role-playing game created by Toby Fox and released in 2015. Its menu and interface audio became familiar to players, and short UI clips like this spread into edits, memes, and parody game menus online. People still use the Undertale select sound because it is instantly readable as a choice or confirmation cue, and it carries the recognizable retro style that makes even simple captions or mock menus feel more playful.