You are trying to add Cisco Expressway to Cisco TMS, but the addition is failing. Which two scenarios might be causing this failure? (Choose three.)

While TMS version compatibility matters for feature support, a version earlier than 12.5 alone is not the documented direct cause of the SNMP-based communication failure described.

Upgrading TMS before adding Expressway is a best practice for version compatibility, but it is not the immediate technical cause of an SNMP-based connectivity failure.

Time synchronization affects certificate validation and federation features, but a time mismatch between TMS and Expressway does not directly prevent the initial SNMP-based addition of Expressway to TMS.

Cisco TMS uses SNMP to poll and manage Expressway; if SNMP is not enabled on the Expressway, TMS cannot query the device and the addition will fail with a communication error.

UDP port 161 is the standard SNMP polling port; if this port is blocked on the network between TMS and Expressway, SNMP queries will not reach the device, directly preventing TMS from completing the addition.