Context: Plus , I got to hear the worst riddle I ' ve ever heard from a bum . " What 's the best nation there is ? " " Uh , Kenya ? " " No , a donation . "

Question: What may be the reason for a bum giving them a riddle ?
Options:
0. None of the above choices .
1. To let them through .
2. To test their knowledge .
3. To earn money from them .
Answer: 3