Which of the following represents a complete sentence?
a. independent clause
b. prepositional phrase
c. subordinate clause
d. stand-alone subject

The answer is (a.) independent clause
An independent clause or usually referred as the main clause is a clause that can stand by itself as a sentence. The independent clause can be a complete sentence because it contains a subject and a predicate.

Delegates: representatives who cast votes at a political party's national convention. binding: if a primary or caucus is “binding” that means the delegates won in that contest are legally bound to vote for a particular candidate at the parties national convention.a primary is a preliminary election used to determine a party's nominee for a specific office. the winner of the party's caucus, or primary, wins the party nomination for that state. then the delegates meet at their party's national party convention, which is a formal gathering of all party delegates from all states.