Which of these best describes the function of transformations?

Transformations allow the CUCM call-routing engine to rewrite calling or called party numbers by applying digit masks, adding prefixes, or stripping digits, and are configured on route patterns, translation patterns, and gateways. This normalization capability is essential for ensuring numbers are presented in the correct format expected by downstream devices such as PSTN gateways or remote clusters.

Tags and operatives are components of route filters, which parse specific segments of a dialed digit string (such as area code or office code) to permit or block routing - not the function of transformations.

Discard digits instructions are a specific digit manipulation mechanism used to strip prefix digits, but they represent only one subordinate action within the broader transformation framework rather than defining what transformations are.

Redirecting calls is the function of call forwarding features or translation patterns used for call diversion, not the primary purpose of transformations, which focus on number format modification.