Which statement is true about energy resources' environmental implications?

• A. Renewables emit zero greenhouse gases.
• B. Non-renewables are finite and typically emit more CO2 than renewables.
• C. Renewables have no habitat or land-use impacts.
• D. All energy sources have identical environmental impacts.

Answer: (B)

The main idea is that the environmental impact of energy depends on how much energy is emitted in the life cycle and whether the resource is finite. Fossil fuels are finite, and burning them releases significant CO2 and other pollutants, so their overall greenhouse-gas footprint per unit of energy is typically higher than that of renewable options. Renewable technologies, by contrast, have very low emissions during operation, which lowers their CO2 intensity, though there are some emissions associated with manufacturing, transport, installation, and maintenance. They can also have habitat and land-use effects, depending on the site and technology.

The other statements miss these nuances: renewables are not truly zero-emission when considering their whole life cycle; they can affect habitats and require land or water resources; and energy sources do not all have identical environmental impacts.