The irony in the judge proposing the plan to fool the townspeople into attending the play in chapters 22 and 23 of The Adventures of Huckleberry Finn is best captured by the option: A judge is typically viewed as the height of moral conduct.
Judges are expected to embody fairness, integrity, and moral authority, yet in this scenario, the judge is engaging in deceitful behavior by crafting a scheme to trick people. This contrasts sharply with the expected role of a judge, highlighting the irony of someone in a position of moral authority participating in manipulation and trickery.