To monitor traffic between leaf switches in a Cisco ACI network and support filtering traffic from a Bridge Domain or VRF, the configuration must allow for specifying the traffic of interest based on tenant, application, and EPG. Option C, filter tenant t1 application app1 epg epg1, meets these requirements by defining a filter that targets traffic from a specific EPG within an application profile in the tenant 't1'. This filter can be applied to the monitoring session to capture the relevant traffic.
References := For detailed procedures on implementing monitoring sessions in Cisco ACI, refer to the Cisco Data Center Core Technologies documentation, particularly sections covering ACI traffic monitoring and filtering.