Final answer:
Retargeting ads are designed to target users who have previously visited a website, aiming to reel in potential customers who showed interest but did not initially make a purchase.
Step-by-step explanation:
When describing how retargeting ads work, the true statement is that they target users who have visited a website before. Retargeting is a form of online advertising that serves tailored advertisements to individuals who have already shown an interest in a website or platform. Unlike traditional advertising which might focus on reaching new customers, retargeting is specifically designed to reach those who have previously engaged with a product or service but did not make a purchase or take a desired action. This strategy can be executed across various digital channels, including social media platforms, but it is not limited to them exclusively.