The answer is: irony
Irony occurs when the speaker says the opposite of what he or she means. It is usually used for emphasis or humor.
In the lines, the speaker makes use of irony to intensify someone's description. The person is portrayed in such a conceited and egotistical manner that probably considers the song is about him or her.
The rest of the options are incorrect because paradox is a proposition that leads to an illogical conclusion; simile is the explicit comparison of things of different kinds; and metaphor is a word or phrase attributed to something but which is not literally suitable.