Answer:
A. a narrative poem with a plot and a refrain
Explanation:
Although nowdays, ballad refers to slow sentimental song, its original meaning was, simply put, a poem with a plot.
"The Lonesome Death of Cattie Carroll" is a song written by Bob Dylan and it tells the real life story of Cattie Carroll's murder.
Since this is a ballad, it is pretty straightforward, it doesn't use figurative language, symbols or epic elements, it just tells the story.
It also, as many ballads do, has a refrain, which is a stanza that is repeated throughout a ballad, something like a chorus of the songs.