Which term refers to sustainable construction materials used in ABC's circular model?

• A. Blue plastics
• B. Red cement
• C. Silver glass
• D. Green aggregates

Answer: (D)

In a circular model, the emphasis is on reusing materials and keeping value in the system, which means choosing inputs that minimize environmental impact. Green aggregates fit this idea because they refer to sustainable construction materials used as aggregates—typically produced from recycled or low-impact sources—to replace traditional, virgin aggregates in concrete or other building mixes. This supports closing the loop: waste or by-products become inputs for new construction, reducing waste, saving resources, and lowering embodied energy.

The other labels don’t carry the same meaning in this context. Green aggregates specifically points to sustainable, reusable aggregates in construction, whereas terms like blue plastics, red cement, or silver glass don’t inherently communicate the same focus on recycling, low impact, and circular use of materials.