Which of the following source of energy is different from others?
Plants
The explanation for the correct option:
Option (D) Plants
The explanation for the incorrect options:
Option (A) Coal: It is a fossil fuel formed by the decay of plants and animals millions of years ago.
Option (B) Lignite: Lignite, often referred to as brown coal, is a soft, brown, combustible, sedimentary rock formed from naturally compressed peat.
Option (C) Petroleum: It is a fossil fuel as the decay of plants and animals also obtains it.
Therefore, plants are different from the others. Hence, Option D is correct.