Final answer:
The Securities and Exchange Commission (SEC) is the federal agency that would bring a civil suit against a company that violated securities laws.
Step-by-step explanation:
The federal regulatory agency that would most likely bring a civil suit against a business that broke securities laws is the Securities and Exchange Commission (SEC). The SEC was established to oversee Wall Street and regulate the investment industry. It ensures compliance with legal standards for the disclosure of information relevant to publicly traded securities and prevents practices such as stock manipulation and insider trading. This aligns with the SEC's role to enhance market integrity and protect investors.