You’ve decided to run a new Google Video campaign with an awareness goal. Why should you opt into Google Video partners?

Because it can give you access to more engagement metrics to measure the impact of the campaign.
Because it can extend the reach of video ads to YouTube Live streaming and Premieres.
Because it can give you access to engage with audiences on the YouTube mobile homepage.
Because it can extend the reach of video ads to a collection of leading publisher sites and apps.

The correct answer is:

Because it can extend the reach of video ads to a collection of leading publisher sites and apps.