Which of the following metrics are generated from first-time customers and help advertisers understand ad-attributed purchases?

The correct answer is New-to-brand metrics because these metrics specifically track the behavior of first-time customers and measure how many of them make purchases attributed to advertising efforts. By focusing on customers who are new to a brand, these metrics provide valuable insights into the effectiveness of advertising in attracting new buyers and expanding brand reach. In contrast, reach and frequency metrics primarily deal with how many people see an ad and how often, while success metrics encompass a broader range of performance indicators, making New-to-brand metrics the most relevant choice for understanding ad-attributed purchases from first-time customers.