An advertiser who wants to target specific categories of video content on the Display Network should:

A) add the keyword “video” to the campaign
B) add a remarketing list to the campaign
C) use AdWords for video
D) create a Search Network with Display Select campaign

The correct answer is:

C) use AdWords for video

Explanation: you can create compelling video campaigns with a range of video ad formats to engage customers in different ways on YouTube and across video partner sites.
Read more here: https://support.google.com/adwords/answer/2375464