In which TrueView format(s) can an advertiser use a companion banner?
A) In-stream and in-display
B) All of the listed answers are incorrect
The correct answer is:
Explanation: A clickable thumbnail image that accompanies a TrueView in-stream ad. On a YouTube page, it appears next to the ad, in the top right corner (on a desktop computer).
Read more here: https://support.google.com/partners/answer/6293542?hl=en