There are no answer choices so I can't be sure exactly what you're looking for, but I'd say paragraph.
A stanza is a group of lines forming the basic recurring metrical unit in a poem, used to separate topics and build a piece of poetry neatly. A paragraph is a distinct section of a piece of writing, usually dealing with a single theme and indicated by a new line, indentation, or numbering. Paragraphs separate thoughts and topics and are a building block for an essay or prose.
