<u> B. Phrases like "black with flies" cause the reader to feel frightened for the little boy.</u>
Pathos, as a mode of persuasion, aims to convince someone on something by appealing to people's emotion, usually by evoking emotions of pity, fear sympathy, or sorrow.
The phrase "black with flies" evokes emotions of fear, and sympathy for the boy, which, depending on the author's purpose, may convince a person of the seriousness of the situation or of getting more involved in the story.
