Campaigns in the United States, Particularly Those for President and Congressional

Campaigns in the United States, particularly those for president and congressional seats, are known for being unusually long due mainly to:

A) the need to reach majoritarian outcomes, in addition to lengthy election calendars.
B) the unusually wide geographic distribution of the American electorate.
C) the need for extensive and consistent media coverage.
D) the need to reach voters and the associated need to raise funds, along with lengthy election calendars.