How does Google Display ads grow marketing results for advertisers?

Questions: How does Google Display ads grow marketing results for advertisers?

It calculates the number of times an ad is effectively run on test websites, then shows the ad on all relevant websites.
It focuses a campaign on either Gmail, TrueView, or Chrome to better isolate specific audiences.
It determines a user’s primary marketing objective and enables the features that will best achieve it.
It harnesses a multitude of signals to place ads against the most relevant content.

This question is from Google Ads Display Certification test.