Which of the following is a fossil fuel?

a) Hydrogen

b) Solar energy

c) Coal

d) Biomass

The correct answer is (c) Coal

Fossil fuels are energy resources formed from the remains of plants and animals buried under the earth millions of years ago. Under high pressure and temperature and in the absence of air, this organic matter slowly changed into coal, petroleum, and natural gas. Therefore, coal is a classic fossil fuel.

Why the other options are not fossil fuels

• (a) Hydrogen: An energy carrier, not a naturally occurring fossil fuel; it is produced from water or natural gas by industrial processes.
• (b) Solar energy: Comes directly from the Sun; it is renewable and inexhaustible, not a fossil fuel.
• (d) Biomass: Energy from recently living matter (crop waste, dung, wood). It is renewable, not formed over geological time like fossils.