The Earth's outermost rigid rock layer the ___ is composed of plates that float on the ___, the region of the mantle where rocks become hot and soft.
A)upper mantle…inner core
B)asthenosphere…lower mantle
C)plate boundary…lithosphere
D)lithosphere…asthenosphere

Question

Quizplus · Accepted Answer

The lithosphere is the Earth's outermost rigid rock layer composed of plates that float on the asthenosphere, a region in the upper mantle where rocks are hot and soft enough to flow slowly.

The Earth's Outermost Rigid Rock Layer the ___ Is Composed