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 truman doctrine was an american foreign policy whose stated purpose was to counter soviet geopolitical expansion during the cold war. it was announced to congress by president harry s. truman on march 12, 1947, and further developed on july 12, 1948, when he pledged to contain threats to greece and turkey.

the answer is:

carbon dioxide