9. Which of the following is a commercial source of energy? A.Agricultural waste B.Dried dung C.Sun D.Natural gas
Answer: Option D Solution: Energy is broadly classified as commercial and non-commercial energy. Firewood, agricultural waste (straw, etc.) and animals waste (cowdung) are the important components of non-commercial energy.Coal, petroleum products, natural gas and, electricity are the important components of commercial energy. These goods are largely used for commercial purposes in the factories and farms.
