Which definition best describes digit matching?

A.
When a digit is dialed, the Cisco CallManager performs an analysis and looks for matching patterns within the answer-address parameter. It then overwrites the calling-party number or ANI when a match is found.

B.
When a call comes in through an MGCP voice gateway, the gateway matches a dial peer based on the incoming called-number, the calling-address parameter, or the answering number destination pattern.

C.
When a digit is dialed, the Cisco CallManager performs a digit analysis and looks for matching patterns within a route plan. When a match is found, the destination-pattern is appended to the incoming called-number and the result is reported as the CSS_CallingPartyNumber.

D.
When a digit is dialed, the Cisco CallManager performs a digit-by-digit analysis and looks for matching patterns within the route plan.