The correct answers are:
a) provide proof of residency
d) fill out a form
f) register before a given deadline
Voting in the US is a right to all citizens, but it comes with certain specific rules and demands. The first one is registering. Each state, city or county is divided into "precincts", which are voting districts, and in other to vote people need to register at the nearest precinct or even register online, and also respect the deadline, which can even be on election day in some states.
Also, one needs to provide proof of residency, because besides being a resident, states can require various periods of residency before allowing a citizen to vote.
And last, filling out a form is part of the requirements and is related to the registration. You either fill out a form online, or in person when registering at your precinct.
