Earth’s thin, rocky outer layer is its
a. core.
b. mantle.
c. crust
d. outer core.

The correct answer is C) Crust.

Earth is primarily composed of four layer from outside to inside. These layers are as follows-

1) Crust- It is the outermost layer of earth, which comprises of two basic rocks that is granite and basalt. It is hard and thinnest layer of the planet earth.

2) Mantle- It lies beneath crust and it is a thicker layer of very hot and dense rock.

3) Outer core- It lies beneath mantle and it is a layer of low viscosity fluid ( molten form). It is responsible for the magnetic field of earth.

4) Inner core- It is the innermost layer with extremely high temperature and pressure.

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.