Computer Science

Skype, Zoom, and Adobe Acrobat Reader are examples of proprietary software because they are owned by companies and typically have restrictions on modification and redistribution. They are not freeware in the strict sense, as some versions may require payment or have limited free features.

Antivirus, Disk Cleanup, and Backup tools are examples of utility software because they provide system maintenance and optimization functions, unlike firmware or horizontal software. Open-source software refers to licensing, not software type.

WinRAR and IDM are distributed as shareware, meaning they are proprietary software offered for free trial with limited features or time, encouraging users to purchase a license for full functionality.

Public Domain Software is free of cost and has no copyright restrictions, meaning anyone can use, modify, and distribute it without permission. Shareware and Freeware may be free but often have usage restrictions, while Proprietary Software is typically restricted and not free.

Vertical Market Software is designed to meet the specific needs of a particular industry, such as banking or hospital management, unlike Horizontal Market Software which serves a broad range of industries.

Horizontal market software refers to applications that serve a wide range of industries and business types, such as MS Office and Adobe Photoshop, which are used across many sectors. Accounting software can be both horizontal and vertical, but general accounting software is often considered horizontal. The other options are examples of vertical market software, designed for specific industries or functions.

A browser is the software used to access and view webpages by retrieving and rendering content from the internet. The other options do not refer to software that accesses webpages.

Graphic software is specifically designed to create and manipulate pictures, 3D images, and animations, whereas multimedia software includes a broader range of media types but is not solely focused on drawing or animation. Therefore, 'Graphic software' is the most accurate answer.

Free software is defined by the Free Software Foundation as software that grants users the freedom to run, study, modify, and redistribute the software, typically with source code available under a license that ensures these freedoms. This is a matter of liberty, not price. 'Freeware' refers to software distributed at no monetary cost but usually without source code access or permission to modify or redistribute, so it is not synonymous with free software. 'Public Domain software' is software not protected by copyright, meaning anyone can use, modify, and distribute it without restrictions, but it is not the same as free software as defined by the Free Software Foundation because it lacks explicit licensing terms guaranteeing the four essential freedoms. 'Proprietary software' is software that restricts these freedoms. Therefore, none of the options perfectly synonymize with 'free software,' but among the given options, 'Public Domain software' (D) is the closest in spirit to free software in terms of freedom, though it is legally distinct. 'Freeware' (A) is incorrect as it usually lacks the freedoms associated with free software.

Windows 8.1 restored the Start button, which was removed in Windows 8, addressing a major user criticism about navigation and familiarity.