Answer:
a) the common law.
Explanation:
According to my research on the United States justice system, I can say that based on the information provided within the question this constitutes a body of law known as the common law. Which, is made up of all of the cases which have been decided by U.S. judges, as well as by English judges prior to the American Revolution, into a system of justice in which the lower courts must follow the decisions of the higher courts.
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