The correct answer is Mail Merge is used to create and send bulk mail, labels and envelopes.
The Mail Merge functionality in MS Word is used to create and send bulk mails, labels, and envelopes.
Mail Merge is most often used to print or email form letters to multiple recipients.
Using Mail Merge, you can easily customize form letters for individual recipients.
Mail merge is also used to create envelopes or labels in bulk.
Found under the Mailings tab in Word 2016, the mail merge feature allows you to merge individual information (such as names, addresses, titles, and even custom information) with a form letter, email, label, etc.