Although Political Parties Have Traditionally Been Active in General Elections

Although political parties have traditionally been active in general elections, mobilizing voters in support of their candidates, their role has decreased over time because

A) state parties are no longer allowed to raise funds from individuals.
B) general-election campaigns have become more candidate-centered and geared to a candidate's own organization.
C) candidates refuse to run for office with a party endorsement and thus most candidates are technically independent candidates.
D) legislative caucuses that provide funds to candidates are not affiliated with a particular party.