In his famous "I have a dream" speech, Martin Luther King says, "I have a dream" throughout the
speech, and thus, uses this persuasive technique
Rhetorical questioning
Repetition
Antithesis
Parallelism
the answer is B repetition, the repetition in the four words āI have a dreamā landed an effect on people showing that the main thing people remember from that whole speech is āI have a dreamā which a form of vocal persuasion. :)