Concept:Mail merge is the word processing feature that creates multiple personalized copies of one document for different recipients without retyping it.Explanation:Mail merge links a main document to a data source that contains the names, addresses, or other details of many people.It automatically places each person's information into a separate copy of the document.This allows the same letter or email to be sent to many different people quickly.Therefore, the feature described in the question is mail merge.Answer:C. mail merge