The answer is A: repeating keywords for emphasis.
Repetition is a rethorical or literary device that consists of repeating the same words or phrases a few times with the purpose of making an idea clearer, which adds emphasis and stress to the writing and speech. Repetition can be a key tool for speakers in developing style and rhythm. some types of repetition are: Antistasis (words/phrases in opposite sense); Epimone (repeat a phrase/question to stress a point) etc.
