Under the American Legal System,subject to Some Exceptions,costs of Litigation

Under the American legal system,subject to some exceptions,costs of litigation regarding both the plaintiff and defendant:

A) are all paid by the loser.
B) are all paid by the winner.
C) are paid for by each side with the plaintiff and defendant paying for their own legal costs.
D) are totaled by the court and then for fairness, split in half with each side paying an equal amount