What is a closed primary?

A closed primary is defined by the stipulation that only registered party members are permitted to vote in that party's primary election. This system is designed to ensure that only those who have a vested interest in the party's values and platform can influence which candidates will represent them in the general election. By limiting participation to registered members, the party can maintain a certain level of control over its candidates and prevent members of other parties from potentially skewing the selection process.

The other answer choices present different concepts related to primaries. Voters being free to vote in multiple party primaries describes an open primary system, which allows crossover voting. The idea that voters can change their party affiliation at any time relates to the mechanics of voter registration but does not accurately define a closed primary. Finally, the statement regarding open access to all eligible voters regardless of party affiliation also pertains to open primaries, which stands in contrast to the closed primary structure.