Which scenario is NOT within the federal courts' jurisdiction according to the Constitution?

The scenario that falls outside the jurisdiction of federal courts, according to the Constitution, involves cases related to the interpretation of state constitutions. The Constitution primarily grants federal courts authority over matters that arise under federal law, treaties, and the federal constitution itself.

Federal court jurisdiction is established by Article III of the Constitution, which outlines their authority to hear cases arising under the Constitution, federal laws, and treaties. Specifically, federal courts are designed to interpret and apply federal law consistently across states, emphasizing their role in national governance. In contrast, state constitutions are interpreted and adjudicated in state courts, which have the primary responsibility for matters involving state laws and state constitutional issues. Therefore, a case focusing solely on the interpretation of a state constitution does not meet the criteria for federal jurisdiction and is properly heard in state courts.