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

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

Poorly defined requirements are a leading cause of defects and project failure. According to the ISTQB CTFL Acceptance Testing Syllabus and IQBBA FL Syllabus, the quality of requirements plays a critical role in successful solution development and acceptance testing. Requirements must be clear, unambiguous, complete, and testable. When they are vague or ambiguous, stakeholders may interpret them differently, which can lead to incorrect implementations, inadequate testing, and ultimately rework or rejection during acceptance.

Option A is explicitly supported by the ISTQB Foundation Syllabus and IQBBA principles. In contrast:

Option B is incorrect because Agile lifecycles still place great emphasis on requirement engineering, even though requirements evolve iteratively.

Option C misrepresents INVEST: it is a guideline for writing good user stories but does not replace reviews or validation techniques.

Option D is risky and not endorsed by ISTQB. While testers may identify ambiguities, the correct approach is to clarify them with all relevant stakeholders, not make assumptions.

Exact Reference – ISTQB CTFL Acceptance Testing Syllabus (Section 1.3.1):

“Ambiguous, incomplete, or inconsistent requirements increase the risk of misunderstanding between stakeholders, leading to incorrect implementation and ineffective tests.”

Acceptance Test-Driven Development (ATDD) involves early collaboration between stakeholders to define acceptance criteria and tests before development begins. Using business process models in ATDD helps visualize user behavior, align test cases with real workflows, and serve as living documentation.

Option C is the least meaningful argument because:

Business process models abstractly describe workflows and decisions at a business level. While they help clarify requirements and detect requirement-related defects, they do not directly support detecting defects in the application code, which is typically the focus of unit and integration testing, not acceptance testing.

Let’s validate the other options:

A is a strong argument — process models clarify use cases for testers.

B is valid — graphical models help visualize test coverage directly.

D is true — as business process models evolve, they remain valuable artifacts aligned with current system behavior and requirements.

Answer: C. Business process models will make it easier to detect defects in the application code.