Final answer:
The GAO (Government Accountability Office) has the primary authority to develop requirements for federal program compliance audits as per the Single Audit Act.
Step-by-step explanation:
The regulatory body that has the primary authority to develop requirements for performing federal program compliance audits in accordance with the Single Audit Act is the Government Accountability Office (GAO). The GAO is known as the "congressional watchdog" and is an independent, nonpartisan agency that works for Congress. Its responsibilities include auditing, evaluation, and investigation services to provide Congress and the executive agencies with oversight information. It plays a crucial role in ensuring transparency and accountability regarding how the federal government spends taxpayer dollars.