Dreyfus is an advertiser looking to drive purchase for his brand'sproducts. Which metrics would be best for evaluating his campaign's purchase goals? (Select2)

Units sold directly measures the number of products purchased, making it the most direct and effective metric for evaluating a campaign focused on driving purchase goals. While click-through rate (CTR) indicates engagement with an ad, it doesn't directly translate to a purchase. A high CTR doesn't guarantee sales, as users might click but not convert. Impressions served only indicates how many times an ad was displayed, not whether it led to any user interaction or purchase. Therefore, for a purchase-driven campaign, focusing on units sold provides the clearest picture of success.