Which of the following is NOT considered a subgenre of writing?

In the context of writing genres, subgenres are specific categories that fall under broader genres. Memoirs, short stories, and persuasive essays are all recognized forms of writing with distinctive characteristics and purposes.

Memoirs present personal narratives focusing on significant life experiences, enriching readers with insights into the author's life. Short stories are concise fictional narratives that typically involve a single theme, character, or conflict, allowing for a complete arc within a brief format. Persuasive essays aim to convince readers of a particular viewpoint or argument, employing logic, evidence, and rhetorical techniques.

Diaries, while a form of personal writing, are generally considered a format rather than a defined subgenre of literature in the same way the others are. They record daily thoughts, events, and feelings without the structured narrative or thematic focus seen in memoirs, short stories, and essays. This distinction keeps diaries outside the conventional classification of subgenres within narrative writing, thus making it the correct choice for which is not considered a subgenre of writing.