In which instances does the Supreme Court have original jurisdiction?

The Supreme Court has original jurisdiction in specific types of cases as outlined in the Constitution. One of the primary instances where this applies is in cases affecting ambassadors, other public ministers, and consuls, as well as in disputes between states. This original jurisdiction is established in Article III, Section 2 of the U.S. Constitution, which specifies these categories.

In the context of the other options, cases involving federal judges fall under appellate jurisdiction rather than original, as they generally pertain to decisions made in lower courts. Civil rights cases may also come before the Court, but these typically do so through appellate jurisdiction, meaning they originate from lower courts. The phrase "all cases reviewed by the Supreme Court" is misleading, as the Supreme Court reviews many cases on appeal or through writs of certiorari rather than exercising original jurisdiction.

Thus, the correct answer highlights the unique cases over which the Supreme Court possesses original jurisdiction, clarifying why it is specifically related to ambassadors and disputes between states.