Which of the following statements explains portability in non-functional requirements?

• A. it is a degree to which software running on one platform can easily be converted to run on another platform
• B. it cannot be enhanced by using languages, os’ and tools that are universally available and standardized
• C. the ability of the system to behave consistently in a user-acceptable manner when operating within the environment for which the system was intended
• D. none of the mentioned