Which agency is responsible for regulating and enforcing safety and health standards?

The Occupational Safety and Health Administration (OSHA) is the agency specifically tasked with regulating and enforcing safety and health standards in the workplace. Established under the Occupational Safety and Health Act of 1970, OSHA's primary objective is to ensure safe and healthful working conditions by setting and enforcing standards as well as providing training, outreach, education, and assistance. By enforcing various workplace safety regulations, OSHA aims to reduce workplace hazards and assure that employers provide a safe work environment for their employees.

The other agencies mentioned have related but distinct roles in public health and safety. The Environmental Protection Agency (EPA) focuses on protecting human health and the environment by enforcing regulations related to environmental hazards. The Centers for Disease Control and Prevention (CDC) is primarily concerned with public health and disease prevention rather than occupational safety specifically. The National Institute for Occupational Safety and Health (NIOSH) conducts research and makes recommendations for the prevention of work-related injuries and illnesses, but it does not have enforcement authority. Therefore, OSHA is the correct answer because it directly oversees the enforcement of safety and health standards in workplaces across the United States.