Question

claim: biomass, or organic matter used as fuel, is an excellent source of clean and renewable energy. it generates far fewer emissions than fossil fuels and reduces our nations reliance on foreign energy sources.

counterclaim: most biomass is produced by burning wood, and since wood is a less energy-dense fuel, it creates more carbon emissions than coal does when producing electricity.

the student who wrote the claim is developing a revised claim as a rebuttal to the counterclaim. which is the best revision?
(1 point)
depending on how they are generated, geothermal and hydroelectric energy can create more emissions than coal when producing electricity.
a wide range of organic materials can be used to make biomass, and sources such as algae are far more energy-dense than wood.
only two percent of the worlds energy is produced using biomass, so we are unaware of what its overall environmental impact will be.
one type of biomass, that is charcoal produced from plant material, can also be used for enriching soil, as it prevents pesticides from leaching and running off.

Explanation:

The best rebuttal directly addresses the counterclaim's focus on wood biomass being low-energy-dense and high-emission compared to coal. It needs to show biomass can be low-emission by using better feedstocks.

1. The first option shifts to other energy sources, not addressing biomass, so it is irrelevant.
2. The second option corrects the counterclaim's narrow focus on wood, noting biomass can use high-energy-dense sources like algae, directly refuting the idea that biomass is inherently higher-emission than coal.
3. The third option is a weak, uncertain statement that does not rebut the counterclaim.
4. The fourth option discusses a secondary use of biomass, not its emissions or energy density relative to coal, so it is irrelevant.

Answer:

A wide range of organic materials can be used to make biomass, and sources such as algae are far more energy-dense than wood.