CTFL-AcT Exam Dumps : ISTQB Certified Tester - Acceptance Testing (CT-AcT)

Performance testing assesses how a system behaves under specific conditions, typically focusing on responsiveness, stability, and resource usage. The type of performance test depends on the workload model:

Load testing evaluates performance under expected peak usage.

Stress testing pushes the system beyond its capacity to assess limits.

Endurance/stability testing checks for performance degradation over extended periods.

Option A correctly describes that performance test types are determined by the workload simulation strategy.

Other options:

B confuses performance with security testing — malicious attack robustness is a security focus, not performance.

C is partly correct but less comprehensive than A. While testing should simulate realistic conditions, categorization into stress/load/endurance is better aligned with workload modeling.

D is misleading — performance tests validate systems against performance requirements; they are not primarily used to define them.

Answer: A. Depending on the model used to simulate the workload, performance tests are called load, stress or endurance / stability tests.

Clear, complete, and testable requirements or user stories are critical for effective acceptance testing. Ambiguities or vague statements lead to differing interpretations by stakeholders, developers, and testers. This often results in software that doesn’t meet user expectations or in tests that fail to verify business needs correctly.

Option B is correct because it highlights the importance of precise requirements in both implementation and testing phases. Ambiguities can result in incorrect behavior, untestable features, or test cases that don’t align with business goals.

Other options:

A is risky — while testers may explore assumptions during exploratory testing, relying on assumptions rather than clarification increases risk.

C is incorrect — the INVEST mnemonic helps write better user stories, but it doesn’t replace review or validation processes.

D is false — Agile still values requirements engineering; it’s more collaborative and incremental, with the product owner playing a key role, not diminishing its importance.

Answer: B. Vague or ambiguous requirements may lead to misunderstandings both during implementation and testing

ISO/IEC 25010 defines two key quality models:

Product Quality Model (e.g., Usability, Security, Portability)

Quality in Use Model — which includes characteristics of the user’s experience when interacting with the product in a real-world context.

The four main characteristics of the Quality in Use model are:

Effectiveness

Efficiency

Satisfaction

Freedom from risk

Option A — Efficiency is one of the key Quality in Use characteristics, as it refers to the resources used to achieve goals with accuracy and completeness.

Other options:

B (Usability), C (Compatibility), and D (Portability) are characteristics of the Product Quality Model, not of Quality in Use.

Therefore, the correct answer, as per ISO 25010:2011, is:

Answer: A. Efficiency