Which sphere includes glaciers and sea ice?

• A. The cryosphere.
• B. The hydrosphere.
• C. The biosphere.
• D. The geosphere.

Answer: (A)

The key idea is how the Earth is divided into systems that group related components. The cryosphere is the part of the Earth system that consists of all frozen water and ice—glaciers, ice sheets, sea ice, snow cover, and permafrost.

Glaciers and sea ice are solid water, not liquid water or living things, so they belong in the cryosphere. This sphere specifically captures our frozen water resources and their role in climate and sea level. In contrast, the hydrosphere covers all water in liquid form (oceans, rivers, lakes, groundwater) and water vapor; the biosphere includes living organisms; and the geosphere encompasses rocks and land. So the cryosphere is the correct category for glaciers and sea ice.