Answer:
A. Context
Explanation:
The introduction establishes an argument's context: it informs the audience of the issue at hand, the prevailing arguments from opposing sides and the position.
Your thesis should clearly and specifically state the setting's role in the work and how it is established.
Writing an effective argument follows certain steps: Introduce your argument by setting the context.
Sounds like cultural allusion since it’s an annual festival with a myth.
You’ll have to give the poem so we can see which structure it is :)