The decision in Marbury v. Madison established the Supreme Court's power of judicial review, which enables the Court to declare acts of Congress unconstitutional, bolstering the Court's authority within the U.S. government.
The decision in Marbury v. Madison (1803) strengthened the power of the Supreme Court by establishing its role in exercising judicial review. This principle gave the Court the power to declare an act of Congress unconstitutional, therefore enhancing its role as a check on the legislative and executive branches of government. By asserting this authority, Chief Justice John Marshall set a precedent that would define the balance of power between the branches of the U.S. government.
Marshall's ruling clarified that while William Marbury was entitled to his commission, the section of the Judiciary Act of 1789 that allowed the Supreme Court to issue writs of mandamus expanded the Court's original jurisdiction beyond what was outlined in Article III of the Constitution. The Court's ability to review Congressional acts was asserted through the denial of Marbury's request, since the Supreme Court did not have the original jurisdiction to issue the writ, making that part of the Judiciary Act unconstitutional. Thus, the correct answer to the question is: D. It established the Court's right to declare an act of Congress unconstitutional.