Final answer:
Non-functional requirements define the attributes and qualities of a system rather than specific behaviors. The non-functional requirements among the options are Security, Logging, Storage, and Performance. Search option is a functional requirement, as it specifies a function of the system.
Step-by-step explanation:
The student's question relates to identifying which items listed are non-functional requirements. Non-functional requirements refer to the attributes of a system that do not do specific tasks but define the system's properties, criteria, or qualities. They are crucial as they deal with the user experience and the sustainability of the system. For the given options:
- Security - This is definitely a non-functional requirement as it defines how the system is protected against unauthorized access and potential threats.
- Logging - This is also a non-functional requirement, as it pertains to recording data about the operation of a system for diagnostic or auditing purposes.
- Storage - Though this could be seen as a functional requirement because it's a clear need for systems to store data, it is often categorized as a non-functional requirement as well because it deals with how much data can be stored, which is more about the capacity and performance of the system.
- Search option - This is a functional requirement because it describes a specific behavior or function of the system, namely the ability to search through invoices.
- Performance - Performance is a non-functional requirement because it refers to the system's responsiveness, scalability, and stability under a particular workload.