Free ISTQB® Certified Tester – Model-Based Tester (CT-MBT) Practice Questions

Sample Practice Questions

Try these 10 sample questions from the ISTQB® Certified Tester – Model-Based Tester (CT-MBT) practice bank. Each includes the answer and explanation. Continue with the interactive practice above to review the full question set.

1. 1A team buys an MBT tool before agreeing what improvement it wants to measure. Which missing step makes this introduction approach premature?

   1. A.Defining measurable objectives for improving the test processCorrect answer: A
   2. B.Choosing the final execution order of every generated test
   3. C.Replacing the existing test techniques with model simulation
   4. D.Completing production deployment before modeling requirements

   Explanation: The syllabus states: "Appropriate tool support is essential for the success of MBT, but acquiring the tool should not be the first step. Instead, the decision to introduce MBT should be based on the definition of measurable objectives regarding test improvements. MBT impacts the whole test process (section 1.2). Therefore, introducing MBT requires strong support from management to lead the process and tool changes in the organization." The introduction decision needs measurable improvement objectives and organizational support. Execution ordering is a later concern; MBT supports existing techniques, and modeling need not wait for production.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.15, §1.1

2. 2A model includes many internal details that do not affect the project's test objectives. What change best follows the syllabus's advice for keeping the model manageable?

   1. A.Model only system or environment aspects relevant to testing objectivesCorrect answer: A
   2. B.Move irrelevant details to more diagrams while keeping them in the test scope
   3. C.Keep implementation details so the test model becomes the full design specification
   4. D.Let generator defaults determine the relevance of details instead of test objectives

   Explanation: The syllabus states: "What quality characteristics of the test object will be modeled? Most commonly the focus is on functionality, but performance factors and other non-functional aspects such as security can also be part of the MBT model. To keep the models manageable and the MBT-based test process efficient, it is recommended to model only the aspects of the system or its environment that are relevant for testing and for the test objectives." Manageability follows from relevance to the test objectives. Redistributing irrelevant detail, changing the model's purpose or substituting generator defaults does not establish that relevance.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.20, §2.1

3. 3A project selects requirements R1, R2 and R3 for coverage. Tests T1 and T2 together cover R1 and R2, but no selected test covers R3. What is still needed for full coverage of this selected requirements set?

   1. A.A test covering R3 at least onceCorrect answer: A
   2. B.A second execution of a test covering only R1
   3. C.A test covering a requirement outside the selected set
   4. D.A test covering R1 and R2 together but still omitting R3

   Explanation: The syllabus states: "Requirements linked to the MBT model This criterion requires that MBT model elements be linked to selected requirements. Full requirements coverage corresponds to a set of test cases that completely covers a selected set of requirements (each requirement is covered by at least one test case)." Every selected requirement must be covered at least once. Repeating or combining R1/R2 coverage, or adding an unselected requirement, does not cover the missing R3.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.28, §3.1

4. 4A generated test describes a valid customer category and an expected outcome, but gives no concrete input values or detailed execution steps. How should it be classified?

   1. A.A low-level test case ready for direct execution
   2. B.A high-level test case at an abstract levelCorrect answer: B
   3. C.An execution log with observed results
   4. D.A concrete adaptation-layer implementation

   Explanation: The syllabus states: "• High-level test cases are test cases without concrete (implementation level) values for input data and expected results. They also do not specify test steps in fine detail. • Low-level test cases are test cases with concrete (implementation level) values for input data and expected results, and with very detailed descriptions of test steps. MBT models can contain different levels of abstraction addressing different output work products to be generated and also addressing different stakeholders. For example: • • High-level test cases may be targeted for review by business analysts Low-level test cases may be directly executed by testers MBT generated high-level test cases provide information regarding test conditions, input data and expected results without concrete values. The test information is expressed at an abstract level, for instance: • • It may define the test procedures with sequences of high level test actions instead of the detailed and completely defined test actions. It may provide equivalence partitions instead of concrete representatives of the partitions." High-level cases omit concrete values and fine-grained steps. A low-level case supplies those details; a log records execution and an adaptation layer implements connections.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.33, §4.1

5. 5An organization wants evidence of improvement before committing to MBT adoption. What belongs in the trial-use stage of the adoption cycle?

   1. A.Define KPIs and run a pilot project to measure improvementsCorrect answer: A
   2. B.Learn more about MBT concepts and potential uses
   3. C.Analyze candidate approaches for applicability in the project context
   4. D.Reinforce organization-wide skill improvements and behavioral change

   Explanation: The syllabus states: "1. Awareness - Establishing improvement objectives in the test process and identifying MBT as a possible technology to address all or some of these objectives. Identifying opportunities for improvement is an important factor in motivating test teams to change the way they work. 2. Interest - Learning more about MBT. 3. Evaluation - Analyzing main MBT principles and existing MBT approaches with respect to their applicability in the given project context. 4. Trial use – Defining key performance indicators (KPIs) and setting up a pilot project to measure improvements. 5. Adoption – Leading and reinforcing change with skill improvements and behavioral change in the organization." KPI definition and a pilot belong to trial use. Learning is interest, applicability analysis is evaluation, and reinforcing organizational change is adoption.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.37, §5.1

6. 6An analyst asks whether useful MBT work must wait until the application is executable. What can the team already do?

   1. A.Generate and analyze test cases from a suitable modelCorrect answer: A
   2. B.Measure the application's actual response time under load
   3. C.Confirm failures by executing the generated tests on the application
   4. D.Compare the application's observed outputs with expected outputs

   Explanation: The syllabus states: "• The abstraction level of the MBT model makes it easier to identify parts of a system where tests will more likely identify defects or anomalies. • Generating and analyzing test cases is possible before any real system exists." Models allow generation and analysis before a real system exists. Actual timings, execution failures and observed outputs require an executable test object.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.14, §1.1

7. 7A team raises its MBT model's abstraction level to manage complexity. Which trade-off should it anticipate?

   1. A.Test adaptation may become more demanding before executionCorrect answer: A
   2. B.Test adaptation becomes unnecessary for generated tests
   3. C.Every stakeholder will automatically understand the new model
   4. D.The model must now contain more implementation-specific details

   Explanation: The syllabus states: "What is the appropriate level of abstraction? Abstraction is useful to master complexity and to focus the MBT model on the test objectives. However, the more abstract the model is, the more demanding is the test adaptation for test execution. Furthermore, the abstraction level often determines the audience/stakeholders who are able to discuss the test design at the given abstraction level." Higher abstraction can simplify the model while increasing adaptation work. It neither removes adaptation nor guarantees stakeholder comprehension.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.20, §2.1

8. 8Which selection criterion uses activities and gateways inside an MBT business-process model as its coverage items?

   1. A.Requirements coverage
   2. B.Model coverageCorrect answer: B
   3. C.Random selection
   4. D.Project-driven selection

   Explanation: The syllabus states: "MBT model elements Model coverage is based on the internal structure of the MBT model. The tester, test manager or any other role involved defines coverage items and selects the set of test cases that covers a desired quantity of those items. Possible coverage items may be model elements such as: • • • • • States, transitions and decisions in state transition diagrams (see “state transition testing” in [ISTQB_FL_SYL]) Activities and gateways in business process models Conditions and actions in decision tables Statements and conditions in textual models" Activities and gateways are internal model elements. Requirements, random walks and project annotations define different selection bases.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.28, §3.1

9. 9Why can a test adaptation layer help when implementation details differ between system variants?

   1. A.It separates test-case design from variant-dependent implementation detailsCorrect answer: A
   2. B.It replaces the need for expected results in generated tests
   3. C.It makes all variants behave identically for every test
   4. D.It moves the test objectives into the production source code

   Explanation: The syllabus states: "cases, a test adaptation layer is provided which is essentially a wrapper around the test object (similar to the keyword-driven testing approach). Using a test adaptation layer has the advantage to separate test case design from implementation details which may depend on the exact version, variant or configuration of the system under test." The wrapper separates test design from implementation-specific variation. It does not remove expected results, guarantee identical variants or redefine objectives as code.

   Reference: ISTQB CT-MBT Syllabus v1.1 — p.34, §4.1

10. 10A manager estimates MBT ROI using only the first project's tool purchase price. What wider evaluation does the syllabus require?

    1. A.Short-term tool cost offset by the count of created model diagrams
    2. B.Long-term financial balance and quality effects across the test processCorrect answer: B
    3. C.Execution-time savings while excluding modeling and maintenance costs
    4. D.First-project costs while excluding later benefits and test-design quality

    Explanation: The syllabus states: "5.1.1 ROI Factors for MBT Introduction MBT generates costs both during the introduction and the operating phase. For a successful MBT introduction, costs have to be counterbalanced by benefits regarding: • • Net financial balance taking into account the complete test process on a long term scale Test design quality and positive impact on the complete development process Cost, savings and improvements in the test process and the test quality have to be taken into account. Costs (see section 5.2.2): • • MBT introduction Re-occurring MBT costs in the test process" The complete-process long-term financial balance and design/development quality are required considerations. Diagram counts, execution-only savings or initial costs alone omit relevant costs or benefits.

    Reference: ISTQB CT-MBT Syllabus v1.1 — p.37, §5.1