Question :Arrange the following in decreasing order (most important first) of their importance for the welfare of human society. Give reasons for your answer: biogas, citric acid, penicillin and curd.

Question :Arrange the following in decreasing order (most important fi

1.	Question :Arrange the following in decreasing order (most important first) of their importance for the welfare of human society. Give reasons for your answer: biogas, citric acid, penicillin and curd.
Answer» Solution :(a) PENICILLIN: An antibiotic which is used to cure many bacterial diseases. (b) BIOGAS: An ecofriendly source of energy in the rural areas, used as biofuel. Curd: A nutritious and easily DIGESTIBLE food for all age GROUPS. (d) Citric acid: Used as preservative in food items