Which of the following is the default page setup orientation of slide in PowerPoint

The default page setup orientation of slides in PowerPoint is Option B: Landscape. This means that by default, slides are wider than they are tall, which is suitable for most presentations where content typically spans horizontally.
Option A: Vertical is not the default orientation for slides in PowerPoint.
Option C: Portrait is the vertical orientation where slides are taller than they are wide.
Option D: None of the above is incorrect because the default orientation in PowerPoint is indeed Landscape.
Therefore, the correct answer in this context is Option B: Landscape.