Final answer:
To delete all comments in PowerPoint, go to the Review tab, click on the Comments button, select all the comments, and delete them.
Step-by-step explanation:
To delete all comments in PowerPoint, you can follow these steps:
Open the PowerPoint presentation. Click on the Review tab in the ribbon at the top of the window. Click on the Comments button in the Comments section of the ribbon. A pane will appear on the right side of the window, showing all the comments in the presentation.
Click on the first comment in the pane, then hold down the Shift key on your keyboard and click on the last comment. This will select all the comments in between. Press the Delete key on your keyboard or right-click on any of the selected comments and choose Delete. Click anywhere outside the pane to save the changes.