If you use images, such as photographs or clipart, on your slides, you should also credit the source of the image. Do not reproduce images without permission. There are sources for clipart and images that are "public use" according to Creative Commons licensing such as:
Photographs are treated as figures in APA Style. Therefore, the citation for the source of the image is included as a footnote in the figure caption underneath the photograph which includes the figure number and a description. The source of the image obtained is attributed using the following model:
Figure 1. Blah blah blah. From Title of Image, by Author, Year. Retrieved from URL.
Figure 1. Photograph of a sculpture in Cupertino, California. From Infinite Loop II by Kurafire (2007, January 3). Retrieved from https://www.flickr.com/photos/kurafire/343629962/.
Another option for citing image sources is to create a separate slide titled "Photo credits" or "Image Sources". For more assistance on the various ways to cite images in presentations (but not necessarily in APA format), see:
For more assistance in creating figures in APA Style, see the following sections & pages of the Publication Manual, 6th edition:
Option 1: Create a References handout (recommended)
Option 2: Create a References slide (if you only have a few items in your list)