Answer:
The correct answer to the question is option A "None of the mentioned"
Step-by-step explanation:
Functional requirements describe the component of a system by verifying the functionality of the software, defines what function a system is likely to perform. It simply dictates to the system/software on how it must behave. For example, it commands software to display, for instance, User name, total orders placed, and a lot of other commands. It puts the computer/software to describe what the product has to do.
Nonfunctional requirements describe the general quality of a system describing how it works.
In the options above, Maintainability allows modification of applications, robustness allows a system to function well even after an interruption with an error command, and Portability allows easy running and the ability for software to be transferred easily, are all examples of non-functional requirements.
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