The correct answer is B) Cadence.
The balanced rhythmic flow of poetry or oratory is referred to as cadence.
When you are speaking, cadence is the natural flow of words. It is the correct way of speaking, not so fast as when you nervous. If you speak too fast, your audience is not going to understand you or at least understand the important parts of your speech. On the other hand, if you speak too slow, your audience is going to get bored. That is why you need cadence, to vary the speed of your speech with the proper inflection in words or phrases.