Why are the video unable to be displayed?

A merchant has importedYoutube video URLs for all of the product but the videos are not displayed on the storefront.

Why are the video unable to be displayed?
A . The merchant did not assign preview image
B . Youtube videos don’t displays for products, they can only be referencein CMS blocks.
C . The merchant did not assign a role to the preview image
D . The merchant did not enter their Youtube API key into the admin

Answer: D