Final answer:
The United States Geological Survey (USGS) is the U.S. government agency responsible for studying and protecting the environment by providing scientific information on natural hazards, conservation of resources, and ecosystem health.
Step-by-step explanation:
The organization in the United States that studies and assesses the environment to protect it, along with the people affected by any negative changes, is the United States Geological Survey (USGS). The USGS provides valuable scientific information regarding various environmental concerns, including natural hazards, the conservation of natural resources, as well as the health of our ecosystems and the implications of climate and land-use change.