What are the horns of dilemma that Socrates presents to Meletus?

Socrates presents Meletus with a dilemma by questioning whether he believes that Socrates corrupts the youth intentionally or unintentionally. If Meletus answers that it's intentional, then Socrates wouldn't harm his own soul intentionally. If he answers unintentional, then there would be no need for punishment. This creates a contradiction in Meletus's argument.