Answer
To pay money.
Step-by-step explanation
Poll tax is was the money one was supposed to make payment so that can be qualified to vote.This payment was paid when one is registering to be a voter and then required to pay annually after the election .The main aim of imposing this type of tax was for the purpose of preventing the blacks from voting.They were sure that the blacks wont be able to raise the amount required for these taxes so in this case they were denied their right to vote for those they were willing.