What is a key reason to include metaphors in a literary work?

to lengthen a literary work so it can be taught in classrooms easily
to explore humans’ relationships to ideals, inner lives, and environments
to classify literary work into specific categories
to create new and surprising comparisons and deepen understanding

Question

What is a key reason to include metaphors in a literary work?

to lengthen a literary work so it can be taught in classrooms easily
to explore humans’ relationships to ideals, inner lives, and environments  
to classify literary work into specific categories
to create new and surprising comparisons and deepen understanding

anonymous · Answer

D., To create new and surprising comparisons and deepen understanding.