Which program served as a model for workers' compensation in both Europe and the United States?

The program that served as a model for workers' compensation in both Europe and the United States is the Workers Accident Insurance. This system was one of the first attempts to provide financial support and medical care for workers injured on the job. It laid the groundwork for modern workers' compensation programs by establishing a framework where employees, in case of work-related accidents, would receive benefits without needing to prove negligence on the part of the employer.

This approach not only emphasized the responsibility of employers to ensure a safe working environment but also highlighted the importance of social insurance as a means to protect workers and their families. The need for such a system arose during the Industrial Revolution when labor conditions were hazardous and injuries were common. As such, this model influenced various workers' compensation laws across different countries, promoting similar programs aimed at worker protection and welfare.

In contrast, the other options, while they might sound relevant, do not have the historic significance or established precedent that the Workers Accident Insurance program holds in shaping workers’ compensation laws. They may represent modern initiatives or approaches but do not trace back to the foundational principles that defined early workers' compensation systems.