District courts are the only federal courts that a. have original jurisdiction b. use a jury c. use a bailiff d. have appellate jurisdiction

A. have original jurisdiction

Original jurisdiction refers to the power to hear a case for the first time, as opposed to appellate jurisdiction, which is the power of a higher court to review a lower court's decision.

The Code of Laws of the United States of America (shortened to just United States Code or U.S.C.) states it this way:  "The district courts shall have original jurisdiction of all civil actions arising under the Constitution, laws, or treaties of the United States."