Which element of the word program window contains buttons for saving a document and for undoing, redoing, and repeating a change? status bar quick access toolbar title bar home tab?

The answer is the Quick Access Toolbar. However, it is not only for saving files or undoing your work. Containing a set of commands that are independent, this toolbar is actually customizable wherein you could change these icons to the ones you really need and frequently use. By tweaking the settings, you can even add commands to the Quick Access Toolbar that are not in the ribbon (like New, Open and Print).