Answer:
C. Cooling of molten lava and magma
Explanation:
The rocks under the surface of earth are heated at very high temperatures. They melt at these high temperatures and create magma. Magma composition depends upon the elements of the parent rocks. It also contains gases. The elements of earth crust are main elements of magma. When this magma is cooled and hardened, igneous rocks are produced. The formation of these rocks depends upon the following factors:
i) Temperature
ii) Pressure
iii) Water
iv) Parent rock composition
