Which configuration will meet Ajax Corporation’s needs?

The Ajax Corporation is designing an IP telephony network using Cisco MCS 7845 Series servers, each one capable of supporting 7500 devices. The design must meet these requirements:

* be cost-effective
* support up to 7500 phones
* provide a minimal level of redundancy

Which configuration will meet Ajax Corporation’s needs?

A.
five Cisco Unified Communications Manager servers: 1 publisher 1 TFTP server 1 primary subscriber 2 backup subscribers

B.
four Cisco Unified Communications Manager servers: 1 publisher 1 TFTP server 1 primary subscriber 1 backup subscriber

C.
two Cisco Unified Communications Manager servers: 1 publisher and TFTP server combined 1 primary subscriber

D.
three Cisco Unified Communications Manager servers: 1 publisher and TFTP server combined 1 primary subscriber 1 backup subscriber