I’ll say it’s C as my opinion
A. Everyone who lives near that factory seems really unhappy. It must give off a dangerous chemical.
Answer:
Metaphor.
Explanation:
A metaphor is a direct comparison of unlike things. In this case, the comparison is of trees and people. These are unlike things and that makes this a metaphor. Hope this helps :)
It emphasizes that the poem is a symbol of the speaker's love.
Hope that helps you