Answer:
D. To help the reader make a connection to a widely held theme
Step-by-step explanation:
When a poet uses a storyline that is universal or widely known by the public he might use it to help the reader make a conection, because it is easier to make a conection with something that you already know, or to something that you are already familiar with, in this case themes or storylines from the past would be easier to relate and to be engaged with than totally new themes or characters.