Final answer:
Option C, 'Beware Macduff! / Beware the Thane of Fife,' is an example of situational irony in Macbeth.
Step-by-step explanation:
The correct answer is option C: Beware Macduff! / Beware the Thane of Fife. This is an example of situational irony in Shakespeare's play Macbeth. Situational irony occurs when there is a contradiction between what is expected to happen and what actually happens. In this case, Macbeth is warned to beware Macduff and the Thane of Fife, but he ignores the warning and ends up being defeated by Macduff, who is the one to ultimately kill him.
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