Energy resources derived from natural organic materials are called?

Hint: The thing that is derived from natural organic material is made up by decomposing plants and animals. They are found in the crust of earth and contain gases which can be utilized for gaining energy. They take around millions of years to generate and are non-renewable resources.

Complete answer:
Fossil fuel is basically a kind of fuel that is formed from fossils by natural processes like decomposition of plants and dead animals etc. Fossil fuels are non-renewable resources that means their overconsumption may lead to their exhaustion as they are not quickly regenerated. They take millions of years to regenerate. Think that the coal, petroleum we are using today have their roots many millions of years back.
They contain high amounts of carbon and hydrogen and are volatile in nature that means they can evaporate quickly. Examples of fossil fuels include coal, petroleum, kerosene etc. The combustion of these fuels releases a high amount of energy. So, that is the reason they became an environmental concern. As they release greenhouse gases during their combustion, which has severe effects on the environment. But at the same time, they have great importance economically.

So, energy resources derived from natural organic materials are called fossil fuels.

Note:
Fossil fuels are thought to be formed when the organic matter is subjected to high temperature and pressure for millions of years. These fossil fuels help to run automobiles, machinery and are also helpful in the generation of electricity. But these resources are limited in nature, if we overexploit it then it will soon be exhausted.