Answered By: Desk Reference Last Updated: Aug 28, 2020
In terms of Clip Art, see Use of Microsoft Copyrighted Content and Microsoft Services Agreement, particularly 8.1 in the latter. So long as you can meet the terms and conditions outlined particularly in that clause (as well as the rest of the Microsoft Services Agreement - i.e., have a licensed copy of the software, etc.), it is permissible to post your slides with Clip Art, particularly when using a secure repository like Nexus.
For other images, consider https://copyright.uwinnipeg.ca/format-specific-guidelines/images.html You may use images under fair dealing for purposes of review, criticism, satire, parody, private study, research or education. If the images are used within the fair dealing purposes of criticism or review you may use them with proper attribution of the source and accompanied by notes which comment directly upon the images.