A Facebook custom audience is based on:

The correct answer is people who have already expressed an interest in your business.A Facebook custom audience is a targeted group of users created from a business's existing contacts or interactions,such as website visitors,app users,or customer lists.These audiences are composed of individuals who have already engaged with the business in some way, either by visiting the website,interacting with the app,or providing contact information.By leveraging this existing pool of potential customers,businesses can tailor their marketing efforts more effectively,delivering personalized content or promotions to users who have already shown interest in their products or services.This targeted approach increases the likelihood of engagement and conversion,as the audience is already familiar with the brand or has demonstrated a level of interest,making the statement accurate.