Which of the following is a characteristic of an island?

The characteristic of an island is that it is an area of land surrounded by water. This definition captures the essence of what an island is: a piece of land that is completely encircled by a body of water, whether that be an ocean, a sea, a lake, or a river. Islands can vary in size from small landforms to large land masses and can be found in every ocean and sea around the world.

The other options describe different geographical features. Elevated land on all sides refers more to a plateau or highland area, while landlocked by mountains suggests a valley or basin that is enclosed by higher terrain. A section of land rising from the ocean floor could describe a seamount or a part of a continental shelf, rather than a fully surrounded landform like an island. Thus, the option that accurately reflects the characteristics of an island is the one that signifies it as an area of land surrounded by water.