I close the window after open multiple PowerPoint presentations, find that all PowerPoint presentations are closed. If I want to close only one PowerPoint presentation, what should I do?

There are three ways:

(1)    Select a PowerPoint presentation tab, and click the Delete key in the furthest right of the tabbar.
(2)    Directly double-click the PowerPoint presentation tab you want to close.
(3)    Right-click the PowerPoint presentation tab, and click “Close presentation” in the menu.