Which button do you select to add a new slide in PowerPoint?

To add a new slide in PowerPoint, selecting the "New slide arrow" is the appropriate choice. This button is specifically designed for creating additional slides within your presentation, allowing you to choose from different layouts that suit the content you wish to present. By clicking on this button, you are not only able to add a slide but also to directly access various template options, enhancing your ability to structure your presentation effectively.

The other options do not serve the purpose of adding a slide. The reading view button is for viewing slides in a read-only format and does not enable editing or adding new content. The slide show button starts the presentation from the current slide, focusing on presenting rather than editing. The normal view button provides access to the editing interface but does not directly initiate the addition of a new slide; this view is simply the workspace for arranging and editing your slides. Therefore, the "New slide arrow" is distinctly the right choice for the task of adding slides in PowerPoint.