Question

what layer of earth heats the lower mantle?
a crust
b lithosphere
c asthenosphere
d core

Explanation:

The Earth's core, which is extremely hot (due to radioactive decay and residual heat from Earth's formation), transfers heat to the lower mantle. The crust is the outermost layer and relatively cool. The lithosphere includes the crust and upper - mantle rigid part. The asthenosphere is a semi - molten part of the upper mantle.

Answer:

D. core