You are presented with the question "What excites the central nervous system?" and the following answer choices: 
- motion
 - competition
 - eating
 - learning
 - heat
 - caffeine
 - sweating
 - turkey

Now knowing that caffeine is a central nervous system stimulant and men seek the excitement of stimulants, because, for the time, the results are agreeable, choose the best answer.


 

      caffeine   