Which group is responsible for the regulations regarding Engineer certification?

The Federal Railroad Administration (FRA) is the correct choice because it is the federal agency responsible for regulating and overseeing safety in the rail industry in the United States, including the certification of engineers. The FRA establishes and enforces regulations for various aspects of rail operations, which encompass the qualifications and certification processes for engineers, ensuring that they meet the necessary standards for safe operation of trains.

The other options each serve different roles in transportation and worker safety, but they do not specifically regulate engineer certification in the rail industry. The National Transportation Safety Board (NTSB) investigates transportation accidents and makes recommendations for safety improvements; the Occupational Safety and Health Administration (OSHA) focuses on workplace health and safety regulations across various industries, not specifically rail engineering; and the American Railroad Association primarily serves as a trade association representing railroads, but it does not have the authority to create or enforce regulations related to certification.