This is D, of course because people have rights to privacy, rights to vote and vote free from both intimidation and coercion and everyone who votes is treated equally. (here's a hint) when ever you see a question like this with a choice that says all of the above, It usually really is all of the above.
All of them and all of them are important. We live in a country where our leaders respect the results of the vote. It doesn't always happen everywhere. Anyway that comment should be on the list above.
A and C go together. They were not always true. Chicago has a very dark history about C where intimidation was a standard used on voting day.
Some religions used to have a prohibition on voting. They have come to realize that is not very wise. Sometimes people are forced to vote, even if it is in secret. They have also learned that you can spoil your ballot.
The 15th amendment guarantees that there is no such thing as a fraction vote. Prior to it's passing, there was such a thing.
