Which organization sets regulations for hazard communication in the workplace?

The correct answer is B, as the Occupational Safety and Health Administration (OSHA) is responsible for establishing and enforcing regulations regarding workplace safety, which includes hazard communication. OSHA's Hazard Communication Standard (HCS) requires employers to provide information to employees about hazardous chemicals they might encounter in the workplace. This involves labeling, safety data sheets, and training to ensure that workers can handle and understand the risks associated with hazardous substances.

The other organizations listed have different roles. The Environmental Protection Agency (EPA) primarily focuses on environmental protection and regulations related to pollutants. The National Institute of Standards and Technology (NIST) works on measurement standards and technology that can impact various industries but does not directly regulate workplace safety. The National Institute for Occupational Safety and Health (NIOSH) conducts research and makes recommendations for the prevention of work-related injury and illness but does not enforce regulations. Thus, the regulation of hazard communication falls under OSHA's jurisdiction, making it the correct answer.