How far from the baseline does US jurisdiction extend into navigable waters?

The correct answer is 12 nautical miles, as this measurement reflects the extent of the United States' territorial sea as defined under international law and U.S. regulations. The U.S. claims a territorial sea that extends 12 nautical miles from the baseline, which is typically defined as the mean low water line along the coast. Within this zone, the U.S. has sovereignty, meaning it possesses full control over the waters, airspace, seabed, and subsoil.

This 12-nautical-mile limit is significant for various maritime activities, including navigation, fishing, and enforcement of laws, which are applicable to both U.S. and foreign vessels within this area. This recognition of jurisdiction is essential for Coast Guard operations and international maritime law, as it helps to define where the U.S. can assert its rights and responsibilities.

The other distances listed are not applicable to the U.S. jurisdiction over navigable waters. For instance, 24 nautical miles typically refers to the contiguous zone, where the U.S. can enforce laws related to customs, immigration, and sanitation, but this zone does not extend sovereignty as the territorial sea does.