Correct Answer : Test Specification
Explanation :
Test Planning : In the Test Planning phase, we create or update the test plans document which includes what needs to be tested, how the testing will be done, test strategy, test environment, test methodologies etc.
Test Specification : In the test specification phase, we create or update the test cases on the basis of the Client requirement.
Test Requirement : In the Test Requirement phase, we analysis and validate the client or system requirement.
Test Configuration : Test configuration phase is when we setup the system configuration for required system or product.
Therefore, Test Specification is a correct answer.