What is one part of the judicial branch?

What does this answer mean?

One part of the judicial branch is the Supreme Court. USCIS also accepts the federal courts.

Article III of the Constitution creates one Supreme Court and lets Congress set up lower federal courts. Congress has done that. Today the federal court system has 94 district courts, which are the trial courts where most federal cases start, and 13 courts of appeals, which review decisions from the lower courts. The Supreme Court sits at the top.

The judicial branch is one of the three branches of government, along with Congress and the president. Its job is to explain laws and settle disagreements about them, including whether a law goes against the Constitution.

Federal judges are nominated by the president and approved by the Senate, and they serve during good behavior, which in practice usually means for life.

Each state also has its own courts for state laws, but this question is about the federal judicial branch. At the interview, the simplest answer is "the Supreme Court."