Final answer:
A ballad is a short narrative folk song that tells a story in an objective manner, usually written in quatrains and featuring a distinct plot or story.
Step-by-step explanation:
The term for a short narrative folk song which tells of a single event in an objective unbiased manner is a ballad. Ballads were historically used to transmit stories, often tragic, from one generation to another before the advent of written language. The ballad is commonly composed in quatrains, which are stanzas containing four lines, with a rhyme scheme that often follows ABCB, where the first and third lines contain eight syllables and the second and fourth lines contain six. This form is well-suited to storytelling as it is meant to be both read and heard. Ballads tend to be more narrative and focus on a distinct plot or story, distinguishing them from other poetic forms such as sonnets, which revolve around a volta, or haikus, which are traditionally concerned with nature and have a 5-7-5 syllable structure.