An Interactive Voice Response (IVR) system in a Contact Center environment provides several key functionalities, including:A.Access a database and provide the caller with all the needed information to complete the transaction (Self Service):This allows callers to retrieve information, perform transactions, or resolve issues without needing to speak with an agent, enhancing efficiency and caller satisfaction.E.Caller defines the reason for the call from several menu options:By interacting with IVR menu options, callers can specify the nature of their call, which helps in routing the call to the most appropriate resource or service within the contact center.References:Documentation on Cisco's IVR solutions, such as Cisco Unified Customer VoicePortal, often outlines these and other functionalities provided by IVR systems in contact center environments.

The correct Command Line Interface (CLI) command to set an individual media file to an expired state in Cisco Virtualized Voice Browser (VVB) is:D.set VVB cache stale_cache_entry <cache_entry_url>This command is used to manually mark a specific media file in the cache as stale, forcing the VVB to fetch a fresh copy of the media file the next time it is requested.References:Cisco VVB administration guides and CLI reference documents provide detailed instructions on using CLI commands, including managing cache entries.