Q. How should I cite a TED talk in APA?

The APA Publication Manual, 7th ed. covers this topic in section 10.12, and their Style and Grammar Guidelines give an example of how the videos should be cited: https://apastyle.apa.org/style-grammar-guidelines/references/examples/ted-talk-references.

There is a slight difference between the citations based on where you viewed the video: on the TED site or through a second party hosting service, like YouTube. Technically, you are supposed to cite where you viewed it first, but in reality it doesn't matter, as long as your reader can find the talk again.