Which of the following provides evidence for rock formation by cooling? select the correct answer.
1.crystals in sedimentary rock
2.fossils in igneous rock
3.crystals in igneous rock
4.fossils in sedimentary rock

Its presence provides the evidence for rock formation by cooling.

Explanation:

There is difference of temperature between the different layers of the earth, as the inner most layer which is more likely happens to be the crust has an extreme high temperature, but the amount of material or elements present inside the earth layers is not exposed to the external environment which makes then even more high in temperature.

The lava which we all know has a high value of temperature in it, while it is located deep inside the earth's outer layer in the form molten iron. When due to any disturbance inside the tectonic plates will lead that molten form of iron to go up in the layers and will eventually lead to cooling down of the material, as it will cause the magma to slow down slowly and will cause the formation of molten rocks.

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