On average, how long does it take for a video ad to get approved?

A) 1 business day
B) Video ads are instantly eligible to show on YouTube and the Display Network
C) 2 hours
D) 10 business days

The correct answer is:

A) 1 business day

Explanation: After you create or edit an ad, the review process begins automatically. All aspects of your ad are reviewed, including your headline, description, keywords, and website or app. These aspects are reviewed according to the AdWords advertising policies. Most ads are reviewed within 1 business day, and some ads are eligible to run while in the review.

Read more here: https://support.google.com/partners/answer/1722120?hl=en