Answer:
Layer A is the crust and Layer B is the mantle.
Step-by-step explanation:
The crust is the hardest and hardest layer on earth. It is an external and solid layer, consisting mainly of rocks, soils and a variety of minerals. It can be classified as terrestrial crust, or oceanic crust (when it is below the ocean).
The Mantle, in turn, is located just below the crust and has a more plastic consistency, being a less rigid layer than the crust. The mantle extends to almost half the earth's radius and its apparent "plasticity" is the result of magma.