In what Cisco solution is Simple Network-Enabled Auto Provision technology used?

A.
Cisco Unified Gateway Duplication

B.
Cisco UnifiedCallManager Redundancy

C.
Cisco Unified SRST

D.
Cisco Unified Call Survivability

Explanation:
Ok, check 1-57 and 2-87: Fallback for IP Phones
The Cisco Unified SRST gateway uses Simple Network-Enabled Auto Provision (SNAP) technology to autoconfigure the branch office router to provide call processing for Cisco IP phones that are registered with the router