Why should Google follow the viewability standards set by the US Media Rating Council (MRC)?

Google follows the viewability standards set by the US Media Rating Council (MRC) to ensure advertisers have a reliable metric for whether their ads were actually seen by users. Viewability standards define what counts as an "impression" that a user has had the opportunity to see, typically requiring a certain percentage of the ad's pixels to be on screen for a minimum duration. This helps advertisers understand the true reach and potential impact of their campaigns, moving beyond simply counting served impressions. The other options are incorrect because viewability standards do not directly measure audience targeting success, frequency capping effectiveness, or instances of double-clicking.