Which of the following is NOT a form of irony?

The correct answer is literal irony, as it does not fit within the established categories of irony. Irony typically involves a discrepancy between expectation and reality, which is a central theme in the other forms mentioned.

Verbal irony occurs when a speaker says one thing but means another, often with a tone that suggests the opposite of what is said. Sarcastic irony is a form of verbal irony that is often more biting or scornful, intending to mock or convey contempt. Dramatic irony involves a situation in a story where the audience knows more about the circumstances than the characters do, creating tension or humor from the contrast of knowledge. All these forms rely on an element of contrast or contradiction in understanding or expectation.

On the other hand, literal irony does not convey this contrast; instead, it involves straightforward language without an underlying irony. Thus, it lacks the essential characteristics that define the other three types.