AUser authentication and security requirements are often the same across systems. For example, the systems might have a common requirement that all products must have a single sign-on using Active Directory for user authentication.
BBusiness applications often contain common functionality for which requirements- and perhaps even full implementations-can be reused. Possibilities include search operations. printing, file operations, user profiles, undo/redo. and text formatting
CThe same core set of requirements is used even though there might be some detailed requirement and/or user interface design differences based on the platform. Examples include applications that run on both Mac and Windows or on both iOS and Android.
