Final answer:
The Environmental Protection Agency (EPA) is responsible for enforcing environmental regulations and setting water quality standards in the U.S. The FBI is the main domestic law enforcement agency, while the NSA/CSS focuses on foreign intelligence and surveillance.
Step-by-step explanation:
Understanding the United States Government Agencies
When it comes to environmental protection and regulation, the Environmental Protection Agency (EPA) is the leading federal agency in the United States. Created by an executive order by President Richard Nixon in 1970, the EPA's critical mission is to safeguard human health and the environment. They achieve this by writing and enforcing regulations that stem from laws enacted by Congress. The EPA is also tasked with establishing water quality standards and has the authority to enforce these standards through various measures, including fines and sanctions.
The Federal Bureau of Investigation (FBI) is the chief federal law enforcement agency within the United States, primarily focused on investigations and law enforcement within the nation's borders. The FBI operates under the restrictions of the Fourth Amendment, which protects against unreasonable searches and seizures.
The National Security Agency/Central Security Service (NSA/CSS) is primarily responsible for the collection and analysis of foreign communications and foreign signals intelligence. It operates within the intelligence community and provides information to senior U.S. policymakers. The notable difference with the aforementioned agencies is that the NSA largely focuses on protection against and surveillance of foreign threats.
Each of these agencies, among others like the Central Intelligence Agency (CIA) and the Department of Defense, contribute to the national security and environmental sustainability of the United States. These agencies and their functions demonstrate the vast and diverse bureaucracy of the U.S. government.