Explanation
Functional appropriateness is the degree to which a product or system provides functions that meet stated and implied needs when used under specified conditions1. It is typically tested during system testing, which is the process of testing an integrated system to verify that it meets specified requirements2. System testing is conducted after component testing and before acceptance testing, and it covers both functional and non-functional aspects of the system3. References = ISO 25010, section A.1; ISTQB Advanced Level Test Analyst Syllabus 2019, section 1.3.1; Test Automation Fundamentals, section A.1.