Unable to select requirement collection
One answer
Requirement collections link to test plans. Requirements link to test cases.
See Linking to requirement collections: "You can ensure that your testing effort adequately covers the necessary requirements by linking requirement collections to your test plans. Later, you can assign each requirement to a test case and link to the test case from the test plan to ensure that the requirements have complete testing coverage."
See also Associating test cases with requirements.
See Linking to requirement collections: "You can ensure that your testing effort adequately covers the necessary requirements by linking requirement collections to your test plans. Later, you can assign each requirement to a test case and link to the test case from the test plan to ensure that the requirements have complete testing coverage."
See also Associating test cases with requirements.