Which of the following is true about biofuels? a. they are made from plant materials and animal fats. b. they are made by directly harnessing energy from the sun. c. they use energy from water. d. they use energy from the earth’s core.

The answer is A. They are made from plant materials and animal fat.

I learned this last year. Bio means animals and plants. Bio FUELS are remains of plants and animals.

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Option A

Explanation:

Bio fuels are derived primarily form plants and animals. There are wide ranges of commercial crops which are cultivated for extracting ethanol (bio fuel) such as wheat, corn, sugarcane, soybean etc.  

Likewise fat of animals is extracted and converted into commercial usable form by hydrogenating them under high pressure and temperature.  

Even the fats obtained from vegetable oil is converted to methanol or any alcohol form hydrogenation

Hence, option A is correct

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