What are initials placed at the bottom of a letter to indicate the writer and/or preparer called?

The initials placed at the bottom of a letter to indicate the writer and/or preparer are known as reference initials. These initials serve to identify the person who composed the document, especially in cases where the writer and the preparer are different individuals. Reference initials are commonly used in professional correspondence to denote accountability and provide clarity regarding document creation, fostering transparent communication within organizations and with clients.

In contrast, a signature represents the personal mark of the writer and is typically used to authenticate or validate a document. A footer is generally used to convey additional information, such as page numbers or other relevant data at the bottom of pages, rather than indicating authorship. An attribution mark is not a standard term associated with letter writing or correspondence. Therefore, the correct answer highlights the specific function of reference initials in identifying the writer or preparer in written communication.