What do you call the writer's complete address, including the date?

The correct answer is indeed the heading. In formal writing, the heading refers to the section at the beginning of a document that contains essential information, including the writer's complete address and the date. This information is crucial as it establishes the context of the correspondence, indicating who is sending the document and when it was written. The heading sets the stage for the reader, ensuring they have all relevant details upfront.

In contrast, the body refers to the main content of the letter or document, where the primary message is conveyed. The footer typically contains supplementary information and is often found at the bottom of documents, while the signature denotes the author's name, affirming their authorship or agreement without necessarily providing contact details or date information.