D. The audience knows the boastful king's power did not last.
Explanation:
Irony is a figure of speech used in literature that will ridicule some situation or person, it shows the contradiction of things. It can be used by choosing a word that express exactly the opposite of its means. The dramatic irony in the poem is the words that appear in the pedestal "Look on my works, ye Mighty, and despair!" but yet nothing was beside the pedestal but only the sand, a desert.
