ISTQB CTFL: Certified Tester Foundation Level (CTFL) v4.0

Last checked November 10, 2026 against the official ISTQB exam page.

1. Question 1Fundamentals of Testing

   A product owner reviews a test summary showing 2,000 test cases executed in the final cycle with no failures. The product owner concludes that the release is defect-free. Which testing principle best explains why this conclusion is not justified?

   1. ATesting can show that defects are present but cannot prove that none remain
   2. BExhaustive testing is required before any release decision can be made safely
   3. CDefects tend to cluster in a few modules, so the rest of the product is safe
   4. DPassing tests prove that every requirement was implemented exactly as the customer intended
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   Correct answer: A

   The principle that testing shows the presence of defects, not their absence, means a clean test run lowers risk without proving the product is defect-free. Exhaustive testing is impossible in practice, defect clustering does not make the rest of the product safe, and passing tests do not prove every requirement is met.

2. Question 2Testing Throughout the Software Development Lifecycle

   A V-model project finds that interface defects between two components are only discovered during system testing, when fixes are expensive. Which change best applies the shift-left principle?

   1. APostpone system testing until acceptance testers have signed off the design documents
   2. BRemove integration testing so that system testing has more time to find interface defects
   3. CDelay all test planning until the code freeze so that testers can work only from the final build and final documentation
   4. DStart integration testing as soon as components are available and involve testers in design reviews
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   Correct answer: D

   Shift-left moves testing activities earlier, so integration testing starts as components become available and testers take part in reviews that catch interface problems sooner. Postponing or removing testing, or delaying planning until code freeze, does not make defects cheaper to find.

3. Question 3Static Testing

   Which statement best describes the difference between static testing and dynamic testing?

   1. AStatic testing needs a running test environment, while dynamic testing reviews documents and requirements only
   2. BBoth static and dynamic testing require test data and a configured environment before they can begin
   3. CStatic testing examines work products without running them, while dynamic testing runs the software
   4. DStatic testing finds failures in running systems, while dynamic testing finds defects in documents
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   Correct answer: C

   Static testing reviews work products such as requirements and code without executing them, whereas dynamic testing runs the software and observes its behaviour. The other options reverse the two definitions or wrongly claim that static testing needs an execution environment.

4. Question 4Test Analysis and Design

   A field accepts applicant ages from 18 to 65 inclusive. Which set of test values applies boundary value analysis most directly?

   1. A0, 18, 65 and 100
   2. B18, 30 and 65 as typical valid ages
   3. C17, 18, 65 and 66
   4. D5, 25, 45 and 85 spread evenly across the range
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   Correct answer: C

   Boundary value analysis tests the values at each edge of a partition and just outside it, here 17 and 66 as invalid and 18 and 65 as valid. Typical values, evenly spread values and arbitrary extremes such as 0 and 100 do not focus on the boundaries.

5. Question 5Managing the Test Activities

   A test manager has limited time before a release. The payment module has high business impact and changes every sprint, while the help pages have low impact and rarely change. Which test planning decision best applies risk-based testing?

   1. ASpread the test effort evenly across all modules so that no area is neglected
   2. BTest the help pages first because their tests are quicker to execute and report
   3. CSkip the payment module tests this sprint because the module was already tested in the previous release and is assumed to work
   4. DAllocate most test effort to the payment module, which has higher likelihood and impact of failure
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   Correct answer: D

   Risk-based testing focuses effort where the likelihood and impact of failure are highest, and frequent change raises the likelihood. Spreading effort evenly, testing easy areas first, or skipping a frequently changed high-impact module ignores that risk.