The solid Earth layer consisting of crust and upper mantle is the

• A. Geosphere
• B. Hydrosphere
• C. Atmosphere
• D. Biosphere

Answer: (A)

Think of the Earth in terms of its major spheres: the solid Earth is the geosphere, the water is the hydrosphere, the air is the atmosphere, and all living things make up the biosphere. The crust and the upper mantle form part of the solid, rocky body of the planet, so they fall under the geosphere. The hydrosphere would be all the water, the atmosphere is the gaseous layers around the planet, and the biosphere is all living systems. While the specific outer rigid shell that includes crust and upper mantle is often called the lithosphere, there isn’t a separate option for that term here, and geosphere is the correct broader category that includes those solid parts of Earth.