Eduardo is an advertiser at a major consumer packaged goods company. He is looking to run a cross-promotional campaign to promote products that are frequently purchased together. Which part of Amazon Brand Analytics would be most useful for him to review to best understand these trends for his brand?

Market basket analysis is the most useful tool for Eduardo because it identifies products frequently purchased together by the same customer. This directly addresses his need to understand co-purchase trends for a cross-promotional campaign. Retail insights provide broader sales and performance data but don't specifically highlight co-purchasing patterns. Traffic diagnostics focus on website traffic sources and performance, not product relationships. Geographic sales metrics show where products are sold, which is irrelevant to understanding which products are bought together.