The correct option is C: "United States Environmental Protection Agency".
<u>EXPLANATION:</u>
The United States Environmental Protection Agency is the body in United States that studies and assesses the environment and how changes in the environment affect the people in a negative manner.
The agency is an "independent agency" that was established in the year 1970 for environmental protection. The work of the agency is to perform environmental assessment, research and education.
The agency works for prevention of pollution as well as conservation of energy. The agency works closely with several industries and also government agencies at all levels.