Recycling solid wastes is an example of..
a) utilizing covercropping techniques
b) preventing erosion in a landfill
c) eliminating sulfur pollutants in the atmosphere
d) conserving natural resources without harming the environment

The correct answer should be D) conserving natural resources without harming the environment

Instead of using new resources, you can use the waste from previous production and recycle it for the sake of creating something else, which preserves the resoruces and doesn't harm the environment.