Extreme exaggeration is:

a. Simile

b. Metaphor

c. Hyperbole

d. Personification

c. hyperbole is the correct one

C. hyperbole

Hyperbolas are now commonplace in language today (think of how often, or at least I do, you might say "This is best tv show ever!" when you might just mean that you like the tv show. Or how we say repeatedly "This is the best day", when there can only be one "best day".)