Read the excerpt from the Prologue of Antigone, by Sophocles. [ANTIGONE and ISMENE enter from the central door of the Palace.]

ANTIGONE: And now you can prove what you are:
A true sister, or a traitor to your family.

ISMENE:
Antigone, you are mad! What could I possibly do?

ANTIGONE:
You must decide whether you will help me or not.

ISMENE:
I do not understand you. Help you in what?

ANTIGONE:
Ismene, I am going to bury him. Will you come?

After reading the passage and the excerpt from the Prologue, describe Sophocles' use of dramatic irony.