Question

Coal is formed from the remains of

• A. Vegetation only
• B. Animals only
• C. Both vegetation and animals
• D. Neither vegetation nor animals

Answer 1

The correct option is A

Vegetation only

An explanation for the correct option

(A) Vegetation only

• Coal is made up of Carbon$\left(\mathrm{C}\right)$, Hydrogen$\left({\mathrm{H}}_2\right)$, Oxygen$\left({\mathrm{O}}_2\right)$, Nitrogen$\left({\mathrm{N}}_2\right)$, Sulphur$\left(\mathrm{S}\right)$, moisture, and incombustible mineral matter (i.e., ash).
• Coal is formed from the remains of plants buried beneath the crust of the earth. Over time, geological actions change the chemical and physical properties of the remains to create a solid material i.e. coal.
• The energy in coal comes from the energy stored in giant plants, which lived in swamp forests hundreds of millions of years ago.
• Coal is grey or a brownish-black sedimentary rock ready to be combustible.

An explanation for the incorrect options

• (B) Animal remains are not converted into coal even over a long period of time.
• (C) and (D) are not appropriate answers as vegetation only is the correct answer.

Hence, option (A) is correct as coal is formed from the remains of vegetation only.