The correct answer is D. Novell.
Novell was a computer software company that was founded in 1983. The company was best known for its NetWare operating system, which was the most popular networking software in the 1980s. NetWare was used by businesses and organizations of all sizes to connect computers and share files and resources.
Microsoft was founded in 1975 and is best known for its Windows operating system. Sun Microsystems was founded in 1982 and is best known for its Solaris operating system. IBM was founded in 1911 and is best known for its mainframe computers.
While Microsoft, Sun Microsystems, and IBM all developed networking software in the 1980s, Novell’s NetWare was the most popular. NetWare was easy to use and reliable, and it offered a wide range of features. As a result, it was the preferred choice for businesses and organizations of all sizes.
In the 1990s, Microsoft’s Windows NT operating system began to gain market share, and Novell’s NetWare began to decline. However, NetWare remained popular in some circles until the early 2000s.