What provides a high-level description of the levels of testing to be performed?

A test strategy is a document that outlines the high-level approach to testing within a project or organization. It defines the testing objectives, the types of testing to be performed at various levels (such as unit, integration, system, and acceptance testing), and the rationale behind choosing those levels. This strategic document serves as a guideline for achieving high-level testing goals and ensures that all stakeholders have a clear understanding of the testing phases and their purposes.

The other options do not provide the same broad overview. A test plan usually details specific activities, resources, schedules, and responsibilities associated with the testing process but focuses more on execution rather than the high-level description of test levels. A test schedule concentrates on the timeline and sequencing of test activities rather than a strategic approach. A test specification generally outlines the specific test cases or conditions that are to be executed but does not provide the higher-level framework necessary for determining the overall strategy for testing across different levels.