What literary device involves exaggerating something for emphasis?

The correct answer is hyperbole. This literary device is characterized by deliberate and extravagant exaggeration used to create emphasis or strong feelings. For example, saying "I’m so hungry I could eat a horse" is an exaggerated statement that emphasizes how hungry someone feels, rather than a literal interpretation.

In contrast, alliteration refers to the repetition of initial consonant sounds in a series of words, which serves to create rhythm or musicality in language. Irony involves a contrast between expectations and reality, often highlighting a surprising or humorous discrepancy. Personification is the attribution of human characteristics to non-human entities, which allows writers to create relatable imagery but does not involve exaggeration for emphasis. Hyperbole stands out as the best choice as it specifically focuses on the act of overstatement for effect.