The correct answer is A. OS/2.
OS/2 (Operating System/2) is a family of multitasking, multiuser operating systems developed jointly by IBM and Microsoft, and later by IBM alone. The first version was released in 1987, and the last version, OS/2 Warp 4, was released in 1996. OS/2 was designed to be a successor to MS-DOS, and it was initially intended to be the standard operating system for IBM’s Personal System/2 (PS/2) line of computers. However, Microsoft and IBM eventually parted ways, and Microsoft developed its own operating system, Windows, which became the dominant operating system for personal computers.
OS/2 is a 32-bit operating system, and it supports a variety of processors, including the Intel 80386, the Motorola 68040, and the PowerPC. OS/2 is a multitasking operating system, which means that it can run multiple programs at the same time. OS/2 is also a multiuser operating system, which means that multiple users can access the same computer at the same time.
OS/2 has a number of features that make it a good choice for business users. For example, OS/2 supports a variety of networking protocols, including TCP/IP, IPX/SPX, and NetBIOS. OS/2 also supports a variety of security features, including user authentication, file encryption, and access control lists.
OS/2 is no longer a widely used operating system, but it is still used by some businesses and organizations. OS/2 is also used by some people who prefer its stability and security over other operating systems.
The other options are incorrect because they are not produced by IBM.
- Windows is a family of operating systems developed by Microsoft.
- DOS (Disk Operating System) is a family of operating systems developed by Microsoft for personal computers.
- UNIX is a family of multitasking, multiuser computer operating systems that exist in many variants.