Which statement best describes the environmental outcomes of the four waste-management options: recycling, composting, incineration, and landfilling?

• A. Recycling reduces waste but does not affect emissions.
• B. Composting reduces waste but increases emissions.
• C. Landfilling generates methane.
• D. Incineration reduces waste and can generate energy but also produces emissions.

Answer: (D)

Waste management outcomes are best understood by balancing how much waste is reduced, what energy or material recovery occurs, and what pollutants are produced. Incineration, especially with energy recovery, can greatly cut the volume of waste needing disposal and provide usable energy, but it also releases combustion emissions that must be controlled. This combination—volume reduction plus energy generation alongside emissions—is what makes the statement about incineration the most accurate overall. Recycling and composting do reduce waste, but their emissions profiles depend on process details and management; landfilling consistently produces methane from anaerobic decomposition, with broader environmental concerns like leachate. So the option that captures waste reduction, energy recovery, and emissions for incineration best describes the environmental outcomes.