Which of the following is an example of a "Commercial" source of energy?
- Coal
- Cowdung cake
- Firewood
- Petroleum
- Electricity
Answer & explanation
Correct answer: option 1
Commercial sources are coal, petroleum and electricity as they are bought and sold. Whereas, non-commercial sources of energy are fuelwood, agricultural waste and dried dung. These are non- commercial as they are not available in the market on a large scale.