Which statement about technology implementation strategy is true?

A.
Cisco Unified Communications Manager Express can be configured to function with no Cisco Unified Communications Manager cluster in the enterprise.

B.
Cisco Unified Communications Manager Express in SRST mode can be configured to function with no Cisco Unified Communications Manager cluster in the
enterprise.

C.
SRST can be configured to function with no Cisco Unified Communications Manager cluster in the enterprise.

D.
SRST and MGCP fallback can be configured to function with no Cisco Unified Communications Manager cluster in the enterprise.