How did personal computers change the landscape of computer usage in the 1970s?

The development of personal computers in the 1970s fundamentally transformed computer usage by increasing direct access to computing for the average person. Before this time, computers were largely confined to large institutions, universities, and corporations, and they required specialized knowledge to operate. The emergence of affordable personal computers made it possible for individuals and small businesses to own and use computers, which democratized access to technology.

With personal computers, people could use software for various tasks, from word processing to basic computing applications, thus enabling them to perform activities that previously required larger systems and technical expertise. This shift not only broadened the user base of computers but also spurred creativity, innovation, and productivity at the individual and grassroots levels, leading to the widespread adoption of personal computing in everyday life.

The other options reflect misconceptions about the role of personal computers in that era; they did not make computers larger or more complex, nor did they centralize computing tasks or entirely remove the need for professional programmers, which still play a crucial role in developing software and systems.