Which option is not aligned with green chemistry principles?

• A. Designing safer chemicals
• B. Reducing waste
• C. Using toxic reagents when needed
• D. Energy-efficient processing

Answer: (C)

Green chemistry aims to minimize hazard and environmental impact throughout a chemical process. Designing safer chemicals reduces toxicity to people and ecosystems; reducing waste lowers the amount of material that must be managed or released; energy-efficient processing cuts energy use and related emissions. Using toxic reagents when needed runs counter to these goals because it heightens safety risks, increases potential exposure, and complicates waste management. It also makes it harder to meet the aim of safer, greener alternatives and processes whenever possible. So, the option advocating toxic reagents when necessary is not aligned with green chemistry principles.