You’ve been running a campaign for your client across several platforms that include desktop web, mobile web, and mobile app. Upon reviewing their campaign, you observe that mobile-specific metrics aren’t showing.What might be the reason for such an error?

The correct answer is that mobile reporting dimensions weren’t included in Report Builder. To see mobile-specific metrics in Campaign Manager 360 reports, you must explicitly include relevant mobile dimensions (e.g., "Device Type," "Operating System," "Environment") when building or customizing your report. Without these dimensions, the report won't break down data by mobile categories, even if mobile impressions and clicks occurred. The other options are incorrect because: "The campaign only had 'mobile app' as a platform filter" and "The campaign only had 'mobile app installs' as a platform filter" describe campaign setup, not reporting issues. Even with these filters, if mobile dimensions aren't in the report, mobile metrics won't appear. "'Mobile website' was not included in the campaign" would mean no mobile website activity, but the question implies activity across platforms, and the issue is about seeing the metrics, not their absence due to lack of activity.