According to Karl Wiegers and Joy Beatty in 'Software Requirements', the distinct levels of requirements are Business, User, and Functional. System requirement is NOT one of the basic distinct levels, as it is often considered a more technical level focusing on the system's implementation.
The student's question pertains to the basic distinct levels of software requirements as described by Karl Wiegers and Joy Beatty in the book Software Requirements, third edition. Looking at the options provided, the basic distinct levels of software requirements they identify are:
- Business Requirements
- User Requirements
- Functional Requirements
- System Requirements
The option that is NOT a basic distinct level of software requirement as per their categorization is System requirement.
Business requirements define the high-level objectives of the organization or customer for the product. User requirements describe what the users need from the system. Functional requirements detail the services the system should provide or the functions it must perform.
The confusion commonly arises because some practitioners consider system requirements to be a synonym for software requirements, encompassing all types of requirements. However, according to Wiegers and Beatty, system requirements are considered a level below software requirements, often focusing more on the technical aspects of the system's implementation.