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

Equivalence Partitioning (EP) is a black-box test design technique that divides input data into valid and invalid partitions, where each partition is expected to exhibit similar behavior. In the context of acceptance testing, EP is especially effective because it helps validate whether a system behaves correctly for representative input ranges defined in the acceptance criteria.

Acceptance testing aims to confirm that the system meets business requirements and handles inputs as expected. EP allows the tester to cover a large input space using fewer test cases while maintaining a high level of effectiveness. It supports efficiency, broad coverage, and relevance to user expectations.

Other options are less suitable:

A. Static code analysis is a white-box technique, more relevant to unit or integration testing.

B. Input validation is an objective or activity, not a test design technique.

D. Defect-based testing is more diagnostic, used after failures or during exploratory testing — less structured for planned acceptance testing.

Exact Reference – ISTQB CTFL Acceptance Testing Syllabus (Section 2.4):

“Black-box techniques such as equivalence partitioning and boundary value analysis are suitable for deriving acceptance tests from user stories or business rules.”

Comprehensive Detailed Explanation (Approx. 200 words):

Acceptance criteria are an essential part of requirements engineering and test design. According to the ISTQB CTFL Acceptance Testing Syllabus, acceptance criteria are defined as a set of statements that specify what must be true for a system, feature, or user story to be considered acceptable to stakeholders. These criteria are used as the basis for developing acceptance test cases and help bridge the communication between stakeholders, business analysts, developers, and testers.

They are not exclusive to Agile frameworks (contrary to option A); while common in Agile (e.g., as part of a user story), they are equally valuable in traditional lifecycles. Option B is incorrect because testers are encouraged to collaborate in defining acceptance criteria early to ensure testability and clarity. Option C incorrectly states that acceptance criteria replace acceptance tests in ATDD (Acceptance Test-Driven Development). In fact, acceptance criteria are transformed into acceptance tests during ATDD.

Exact Reference – ISTQB CTFL Acceptance Testing Syllabus (Section 2.1):

“Acceptance criteria describe the conditions under which a requirement, user story, or business process is considered successfully implemented. They provide the foundation for acceptance testing and serve as input to test case development.”

Therefore, option D is the most accurate.

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.”