[ Law & Ethics ] Open Question : non- compete clause in contracts are:?

non- compete clause in contracts are: A) never enforced because they violate antitrust laws B) never enforced because they are unethical C) always enforced under the doctrine of "freedom of contract" D) sometimes enforced if they are reasonable

Source: http://answers.yahoo.com/question/index?qid=20120618175846AA6kuDv

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