Hello Samuel,
The navigation block acts as a progress bar and more. Not only does it show which questions have been answered, but also whether each answer is correct, incorrect or incomplete, whether a description question has been viewed, whether an essay type question is saved, etc.
Note that normally the block is displayed at the top right of the page but, the page being responsive, depending on the width of the window and the zoom value, it can move to the bottom of the page.
