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.”

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

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.