To answer this question, let's go through each option to understand why it is correct or incorrect:
Option A) To ensure that the test case specification is complete - This option is incorrect because the purpose of test completion criteria is not to ensure the completeness of the test case specification. Test completion criteria are used to determine when to stop testing, not to evaluate the completeness of the test case specification.
Option B) To set the criteria used in generating test inputs - This option is incorrect because the purpose of test completion criteria is not to set the criteria for generating test inputs. Test completion criteria are used to determine when to stop testing, not to set the criteria for generating test inputs.
Option C) To know when test planning is complete - This option is incorrect because the purpose of test completion criteria is not to determine when test planning is complete. Test completion criteria are used to determine when to stop testing, not to assess the completion of test planning.
Option D) To plan when to stop testing - This option is correct because the purpose of test completion criteria is to establish the conditions or criteria that indicate when testing should be stopped. Test completion criteria help in determining when sufficient testing has been conducted and when additional testing is no longer necessary.
The correct answer is D. This option is correct because test completion criteria are used to plan when to stop testing based on specific conditions or criteria that indicate that sufficient testing has been performed.