Identify the Target Audience: To ensure that the advertisement targets customers in the eastern region, you need to define a specific customer segment that includes customers residing in that area.

Customer Segment Configuration: In Pega's Next-Best-Action Designer, customer segments allow you to group customers based on specific attributes, such as location, ensuring that only the relevant audience sees the offer.

Implementation: Configure the customer segment by setting the geographic criteria to include customers from the eastern region.

Reference: Pega Marketing and Customer Decision Hub documentation emphasize the use of customer segments to personalize and target offers effectively (Pega Customer Decision Hub, Segmentation and Targeting).