Final answer:
The American Recovery and Reinvestment Act included subcontractors in the definition of business associates, broadening the range of entities that must comply with HIPAA regulations.
Step-by-step explanation:
The American Recovery and Reinvestment Act expanded the definition of business associates in the context of health information privacy and security rules to include C. Subcontractors. These are third-party service providers who perform functions or activities on behalf of, or provide certain services to, a covered entity that involve the use or disclosure of protected health information. The expansion of the definition came as part of the Health Information Technology for Economic and Clinical Health (HITECH) Act, which was enacted as part of the broader legislation. This change increased the categories of businesses that must comply with Health Insurance Portability and Accountability Act (HIPAA) regulations.