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

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

Exploratory testing is an unscripted, experience-based testing technique where the tester learns about the system, designs tests, and executes them simultaneously. It is especially effective in Agile environments, where rapid feedback and creative exploration are valuable.

Option D is the least likely action because scripting automated test scripts is a structured activity that typically occurs after exploratory sessions or during more formal test phases. Exploratory testing emphasizes manual exploration, not automation scripting.

Other options:

A is part of the core purpose of exploratory testing — discovering the product.

B is relevant — defining a charter and discussing it with stakeholders (like the Product Owner) helps guide the exploratory session.

C is also relevant — results of exploratory tests should be documented and communicated.

Answer: D. Scripting of the automated test scripts

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