Answer:
D. the narrator's tone of voice
Step-by-step explanation:
The tone of voice is one of the elements with the greatest influence on the seriousness of geographical videos. In each tone of voice there are a series of sound parameters that give meaning, consciously and unconsciously, to the message being transmitted.
The serious tone of voice suggests maturity, seriousness, credibility and generates confidence in others. It is most often used in geographic videos. However, if the tone of voice is extremely serious, it refers to somber sensations