Final answer:
The major networks that dominated the news scene since the 1980s were ABC, CBS, and NBC, known for their extensive reach and nightly newscasts.
Step-by-step explanation:
Since the 1980s, the major networks that once dominated the news arena were ABC, CBS, and NBC. In the early days of television journalism, these networks began featuring nightly newscasts and controlled a large share of what the American audience watched. The presence of these networks was so prominent that their evening news programs drew in millions of viewers, far outnumbering the viewership on cable news channels like FOX News, which emerged later, especially during the 24-hour news cycle era.
While FOX News became a significant player in the news industry, especially through cable television, ABC, CBS, and NBC have historically been the major networks known for their broad audience reach and influence over the public conversation. However, the landscape has changed with the arrival of 24-hour news stations such as CNN, and later, MSNBC and FOX News, with each of these networks providing distinctive editorial commentary combined with their reporting, reflecting different political biases.