Flynn wants to download a custom report from Amazon DSP which will allow him to view the performance on audiences his campaign reached, as well as those not directly reached. Which of the following dimensions should he select for this use case?

To analyze the performance of audiences reached and not directly reached, Flynn should select the "Audience" dimension in a custom report. This dimension provides granular data related to audience segments, allowing him to see how different audience groups performed, including those targeted and those that may have been exposed to the ads without being explicitly targeted. The "Inventory" dimension focuses on the ad placements and publishers, not audience performance. The "Campaign" dimension provides an overview of campaign-level performance but lacks the detailed audience-specific breakdown Flynn requires.