Which of the following best describes the impact of national campaigns on the elections process?
A. They are secondary to state campaigns, as they coordinate with state strategies but do not provide a nationwide framework.
B. They are primarily focused on controlling candidates, preventing them from expressing too much initiative and keeping them within party control.
C. They are in charge of all efforts and strategies by all groups associated with a campaign, including the activities of independent support groups and PACs.
D. They serve as central coordinating systems, providing strategies at all levels while allowing for the independent initiative of local party organizations and independent supporters.