By which feature are island groups identified?

Land areas surrounded by water

An island is a piece of land that is completely surrounded by water. A group of such islands is called an island group or archipelago. The surrounding water may be seawater, as around many coastal islands, or inland water, as around an island in a lake. This defining relationship between land and water is more important than climate, surface colour, or the presence of plants.

The clue in the question asks for the feature used to identify island groups. Land areas surrounded by water match the definition exactly, so option A is correct. Snow-covered plains, dry plateaus, and sand dunes describe possible landscapes but do not define islands. A place may have sand, rocks, or vegetation, but it is identified as an island because water surrounds it on all sides.

This is a Class 9 Geography question. Chapter: Physical Features of India. Topic: Major Physiographic Divisions.