Final answer:
The format of the message is not a key consideration when developing a piece of writing.
Step-by-step explanation:
A key consideration when developing a piece of writing is the format of the message. The format includes the structure and organization of the writing, such as the use of paragraphs, headings, and bullet points. While the purpose of the message, the intended audience, and the timeliness of the message are all important considerations, the format affects how the information is presented and how easily it can be understood by the readers. So option D. The format of the message will be the correct option of the answer.