The correct answer is C. Slide Design.
A slide design is a pre-made set of formatting options that includes a theme, fonts, colors, and effects. It can be applied to a single slide or to all the slides in a presentation.
A slide style is a set of formatting options that includes a font, color, and effect for a specific type of object on a slide, such as a title, bulleted list, or picture.
A slide show is a presentation that is displayed on a computer screen or projector.
A slide format is a set of formatting options that includes the font, size, and color of text, as well as the alignment of text on a slide.