An advertiser's campaign is targeting site visitors, engagement audiences, and actalike audiences. The advertiser wants to see which audience drives the highest click-through rate (CTR). How should the advertiser obtain this report?

To determine which audience drives the highest CTR, the advertiser needs to analyze performance data broken down by audience. The "ad reporting" tab in Ads Manager is the correct place for this. Within the reporting interface, selecting "Audience" under "Targeting Breakdown" will segment the campaign's performance metrics, including CTR, by the specific audiences targeted (site visitors, engagement audiences, actalike audiences). This allows for a direct comparison of CTR across these audience segments. Checking saves is a metric for engagement, not directly for CTR. Setting a conversion window affects how conversions are attributed, not how audience performance is broken down. The audience insights tab provides information about audience demographics and interests, but it does not report on the performance of specific audiences within a live campaign.