A central operations account must view supported CloudWatch telemetry from several member accounts without copying long-lived credentials into dashboards. Which capability should it evaluate?

1. Disable telemetry in source accounts because one dashboard is central.
2. Rename every metric namespace to the monitoring account ID without sharing access.
3. Publish every member account root key in the dashboard JSON.
4. CloudWatch cross-account observability with appropriately configured monitoring and source-account links.