Which requirement is non-functional?
Why A is the answer
The system must respond within 200 milliseconds
Non-functional requirements describe qualities such as latency and availability.
In detail
- A response time describes how well it works, so it is non-functional.
- Latency and availability are qualities.
Use case
An illustrative scenario, not a real incident.
"Users can reset a password" is functional. "Respond within 200 milliseconds" describes a quality, so it is non-functional.
See it in different ways
stateDiagram-v2 [*] --> BusinessNeed BusinessNeed --> Requirements Requirements --> Design: functional and non-functional Design --> Measure: KPIs and ROI Measure --> [*]
flowchart TD
Q{"Is it a behavior or a quality?"}
Q -->|"What it does"| A0["Functional"]
Q -->|"How well it does it"| A1["Non-functional"]Key point: Non-functional means qualities.
Why the other options are wrong
- B. A user can place an order from a phone
- That is a function.
- C. A manager can approve a refund on the page
- That is a function.
- D. A customer can update a delivery address
- That is a function.