Final answer:
The biggest game-changer the film industry faced in the 1980s was the expansion of the home video market, which drastically altered how audiences viewed movies and challenged the existing television and movie industry structures.
Step-by-step explanation:
The most significant game-changer the film industry faced in the 1980s was not the introduction of computer-generated imagery (CGI), the rise of independent cinema, or the emergence of streaming services, but rather the expansion of the home video market. This era saw the VCR and later the DVD become commonplace in households, shifting the way audiences consumed movies. The accessibility of films at home through VCRs allowed people to view movies at their convenience, significantly altering the movie industry landscape. While television technology had been developing since the late 1920s, it was the post-World War II economic boom that saw televisions become a fixture in most American homes. Cable television networks began challenging the major networks for advertising revenue with specialized channels catering to specific audiences, changing the game in the 1980s.