The correct option is Branch.

You should configure Branch policies because Azure Repos provides a built in rule to require a linked work item on pull requests and that rule is applied at the branch level so it enforces the association automatically for protected branches.

Using Branch policies minimizes ongoing administration because you configure the policy once for the target branches and all pull requests that target those branches must meet the linked work item requirement before they can be completed.

The Build policy is not correct because build policies focus on requiring successful CI builds for pull requests and they do not enforce that a work item is linked to the PR.

The Status policy is not correct because status checks allow external services to report pass or fail on a pull request and they do not provide a built in mechanism to require linked work items.

The Check-in policy is not correct and it is less relevant for Git repositories because check-in policies are associated with older TFVC workflows and they are not the standard mechanism for enforcing pull request rules in Azure Repos Git.

Full AWS Practitioner Certification Question