Functional requirements should be traceable back to which type of requirement?

Functional requirements are the specific behaviors or functions of a system that need to be implemented in order for it to fulfill its intended purpose. These requirements are derived directly from business needs and objectives. Therefore, they should be traceable back to business requirements, which articulate what the organization seeks to achieve.

By maintaining this traceability, business analysts ensure that every functional requirement directly supports a specific business goal, making it easier to verify whether the system ultimately meets its strategic objectives. This linkage helps in validating requirements during testing and in ensuring that the development aligns with stakeholder expectations and business value.

While design functions, nonfunctional requirements, and low-level requirements are important in their respective contexts, they do not hold the same foundational connection to the overarching goals of the business, making them less suitable as a basis for tracing functional requirements.