Final answer:
The best option to complete the title of the graphic based on the features and advantages described is c) Open Primaries. Open primaries allow more voter participation and do not require extensive meetings or debates, which encourages higher voter turnout.
Step-by-step explanation:
The option that best completes the title of the graphic, which features being 'Allowed to participate' and advantages such as not involving extensive meetings or debates and encouraging voter participation, is c) Open Primaries.
In an open primary, a registered voter may vote in any party primary regardless of their own party affiliation. This system promotes higher voter turnout because it is inclusive of all voters, regardless of their registered party. It contrasts with closed primaries, where only party members can vote, and caucuses, which generally require more commitment and time from participants.
Advantages of open primaries include increasing voter engagement and reducing the number of extensive meetings or debates that may be characteristic of caucuses. They also allow for greater inclusivity and simplicity in the voting process.