Final answer:
The Wireline Competition Bureau (WCB) and the Federal Communications Commission (FCC) are key departments helping broadband cable systems to expand or rebuild. They foster growth and investment in broadband infrastructure, support fair competition, and ensure broadband access across different regions.
Step-by-step explanation:
The department that plays a key role in helping broadband cable systems to expand or rebuild their networks is known as the Wireline Competition Bureau (WCB). This bureau assists in the policy development for wireline telecommunications, including broadband, to foster growth and encourage investments in infrastructure, markets, and services.
Additionally, the Federal Communications Commission (FCC) has various responsibilities aimed at promoting competition, innovation, and investment in broadband services and facilities.
The FCC also ensures fair competition and that emerging technologies receive the necessary regulatory conditions to thrive. Moreover, the FCC addresses the digital divide by attempting to ensure all Americans have equitable access to quality broadband services, encouraging investment in internet infrastructure to reach underserved areas.