The correct answer is White box testing.

White box testing relies on full knowledge of the internal network architecture, configurations, source code, and security control implementations to plan and execute tests. When written technical documentation is inaccurate or incomplete the tester can be misled about system boundaries and control placements which causes missed test cases and incorrect validation of protections.

Documentation such as network diagrams, asset inventories, firewall rule sets, access control lists, and configuration files directly affect White box testing. If those artifacts are wrong the assessment may skip critical hosts, exercise the wrong controls, or produce false negatives and false positives which reduces the usefulness of the engagement.

Gray box testing uses only partial internal knowledge or limited credentials and it combines internal and external techniques. Because it does not depend on complete documentation to the same degree inaccuracies in written technical documentation are less likely to cause major failures compared with white box testing.

Spectrum box testing is an ambiguous term and is not a standard assessment methodology. It is not the best choice because the question asks which approach is most impacted by documentation errors and a nonstandard term does not match that criterion.

Black box testing treats the target as an external attacker and does not rely on internal documentation. Testers perform reconnaissance and probing to discover assets and controls so errors in the written documentation have minimal direct impact on the conduct of the assessment.

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