Sarah thought that buying beer with a fake idea was a good idea. She just wanted to enjoy herself. But it turned to be anything but. What did it turn out to be?
Options:
- a smart decision
- spend money
- get arrested
- stupidity
- have fun
Please answer and provide answer explanation.

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
One needs to be 21 years or above to buy beer. One's age can be verified using I.D. Faking I.D. is a criminal offense. Committing a crime is stupidity. Stupidity is a type of behaviour. The final answer: stupidity.