The correct answer is B. figurative language.
When writers use literal words, it usually happens in prose - prosaic writers don't always feel the need to embellish their language with a lot of metaphors and personifications, or at least not to the same degree as poets do. On the other hand, poets work with a limited number of words (given that poems are much shorter than texts and novels) so they have to make do with what they've got.
In order to condense their language but still manage to say everything they want, poets often use figurative language (figures of speech such as metaphors, allusions, onomatopoeias, etc.) and that way they can use fewer words so as to express many ideas.