What symbolic meaning do the circles of hell most likely represent in the inferno?

a. they represent the number of days satan lived in harmony with god.
b. they represent the most infamous sinners to ever live.
c. they represent the different levels of sin.
d. they represent the required actions needed to make it to heaven.

The answer is C: They represent the different levels of sin.

Dante´s hell is organized around an interpretation of Aristotle´s writings on vice and virtue, most of which are to be found in the Greek´s Ethics.

As Dante would have it, his hell is divided in nine concentric circles that encapsulate what he believed to be the different levels of sin, all of them relating either to vices of the body and lack of virtue (violence and unbridled appetites) or deformations of the capacities of human reason (malice and fraud against other human beings).