Here is a link to the South Carolina Election Commission’s web page, showing candidates for President who are on the ballot. There will be five presidential nominees on the ballot, those nominated by the Democratic, Republican, Constitution, Green, and Libertarian Parties.
South Carolina has three ballot-qualified parties that only exist in that state, and which didn’t nominate anyone for President. They are the United Citizens Party, the Independence Party, and the Labor Party. In the past the United Citizens Party has nominated presidential candidates. In 2008 it nominated Barack Obama for President. Even though South Carolina permits fusion, though, something went wrong and Obama was only listed on the ballot as the Democratic nominee. In 2000 it nominated Ralph Nader. In 2004 it nominated Walt Brown, the Socialist Party nominee.
Also in the past, the Independence Party nominated Ross Perot for President in 1996, and Ralph Nader for President in 2004. Back in 1996 its name was the Patriot Party.