Explanation: Only Statement 3 is correct

Statement 1 is incorrect: It is the extended margin of each continent occupied by relatively shallow seas and gulfs. It is the shallowest part of the ocean showing an average gradient of 1° or even less.

Statement 2 is incorrect: The shelves are almost absent or very narrow along some of the margins like the coasts of Chile, the west coast of Sumatra, etc. On the contrary, the Siberian shelf in the Arctic Ocean, the largest in the world, stretches to 1,500 km in width.

Statement 3 is correct: Under the United Nations Convention on the Law of the Sea (UNCLOS), the continental shelf is the seabed and subsoil extending up to 200 nautical miles from a coastal state’s baseline or further if the natural margin extends beyond this limit. Coastal nations have exclusive rights to explore and exploit resources on their continental shelf.

Source: TH