Which layer is described as the lower mantle in the provided material?

Which layer is described as the lower mantle in the provided material?

• A. Lithosphere
• B. Mesosphere
• C. Asthenosphere
• D. Core

Answer: (C)

The layer that makes up the deeper part of the mantle is the mesosphere. In Earth’s structure, the lithosphere forms the rigid outer shell, the asthenosphere sits beneath it as a softer, ductile zone, and below that is the lower mantle—the mesosphere—extending down to the boundary with the outer core. So when you’re told the lower mantle is a certain layer, that name points to the mesosphere. The lithosphere is the surface shell, the asthenosphere is the layer just above the lower mantle, and the core lies beneath the mantle.

The layer that makes up the deeper part of the mantle is the mesosphere. In Earth’s structure, the lithosphere forms the rigid outer shell, the asthenosphere sits beneath it as a softer, ductile zone, and below that is the lower mantle—the mesosphere—extending down to the boundary with the outer core. So when you’re told the lower mantle is a certain layer, that name points to the mesosphere. The lithosphere is the surface shell, the asthenosphere is the layer just above the lower mantle, and the core lies beneath the mantle.