The correct option is 3. Enjambment.
When using emjambment, the poet moves from one verse to the other without signalling it with punctuation.
Caesura is a pause in a verse or from one verse to another which is usually signalled by punctuation. Blank verse is a literary device in which iambic pentameter verses but the text does not use rhyme. Lastly, free verse is present when the poem is free from limitations of rhyme, rhythm and meter.
