Where would a call-to-action (CTA) overlay show?
All of the listed answers are correct
On TrueView in-display ads
On videos on your channel
On embedded videos
Call-to-action overlays are eligible to show on any TrueView video ad on YouTube.They’re associated with the video instead of the ad, call-to-action overlays will show whether your video is triggered through an ad or an organic (unpaid) view.
Read more here: https://support.google.com/partners/answer/3013684?hl=en