Which method allows you to add a new slide to a PowerPoint presentation?

The method of clicking the "New Slide" button is a direct and intuitive way to add a new slide to a PowerPoint presentation. This button is typically located in the toolbar, often within the 'Home' tab under the 'Slides' group. Utilizing this method provides an immediate visual confirmation, allowing users to see their options for slide layouts and to choose one that fits the context of the presentation. This streamlined approach is commonly used for its convenience.

Other options, while they involve some sort of slide creation or management, do not specifically accomplish the goal of adding a new slide to an existing presentation as directly as clicking the "New Slide" button does. Dragging an image onto the slide does not create a new slide but instead adds content to the currently selected slide. Selecting "Insert Slide" from the menu may imply adding a new slide depending on the specific version of PowerPoint, but it is less commonly used than the dedicated button. Going to the "File" menu and choosing "New" typically initiates a new presentation rather than adding to an existing one, which is not the objective in this case.