Multiple choice

A glacier is

  1. a snow covered mountain

  2. a rock formed by molten lava

  3. a land surrounded by water

  4. a river of ice

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A glacier is a large mass of ice that forms on land and moves slowly downhill under its own weight, essentially behaving like a river of ice. The other options are incorrect: a snow-covered mountain is simply a geographic feature, rocks formed by molten lava are igneous rocks, and land surrounded by water is an island.