What is the minimum number of independent network WAN links required for clustering

What is the minimum number of independent network WAN links required for clustering over the WAN in the Cisco Unified Contact Center Enterprise solution, when both the Cisco Unified Communications Manager cluster and the related Peripheral Gateway duplex pair are also split across the WAN?

A.
1 – The highly available Cisco Unified Communications Manager and Cisco Unified Contact Center
Enterprise networks can be converged between the sites over a single WAN connection.

B.
2 – The highly available Cisco Unified Communications Manager and Cisco Unified Contact Center Enterprise visible networks can be converged between the sites over one WAN connection. A second WAN connection is required for the combined central controller and PG private network WAN.

C.
3 – The highly available Cisco Unified Communications Manager and Cisco Unified Contact Center Enterprise visible networks can be converged between the sites over one WAN connection. A second WAN connection is required for the central controller private network WAN. A third WAN connection is required for the Peripheral Gateway private network WAN as it cannot be combined with the central controller private network in clustering-over-the-WAN designs.

D.
4 – The highly available Cisco Unified Communications Manager WAN connection must be dedicated to ensure that it meets the 40-ms latency requirement of clustering over the WAN. The Cisco Unified Contact Center Enterprise visible network requires its own visible WAN connection. A third WAN connection is required for the central controller private network WAN. A fourth WAN connection is required for the Peripheral Gateway private network WAN because it cannot be combined with the central controller private network in clustering-over-the-WAN designs.