Which is a correct configuration for Cisco Unity with voice recognition?

Which is a correct configuration for Cisco Unity with voice recognition?

A.
Cisco Unity and Voice Recognition on-box with 24 ports.

B.
Cisco Unity and a separate 24-port voice recognition server.

C.
Cisco Unity and voice recognition on-box with all Cisco Unity ports capable of being voice recognition ports.

D.
Cisco Unity and a separate voice recognition server with up to 144 ports.