Why do you think congress established a court system that allowed appeals to be made to a higher court?

Appellate jurisdiction means that the Court has the authority to review the decisions of lower courts. The United States district courts are the trial courts of the federal court system.  This is where federal cases are tried, where witnesses testify, and federal juries serve.   There are 94 federal district courts in the United States. Most of the cases the Supreme Court hears are appeals from lower courts.

I think it's necessary. We live in a society in the process of building a democracy accessible to all people. Like every process, we are subject to failure. The justice system has been questioned by social movements about their decisions, often considered unfair. In this way, the possibility of appealing to a new analysis of the case is important so that some decisions are reviewed.

the 4th option is the answer

i would say b. research typically uses a variety of sources