Dependabot pull requests for security updates are managed like any other pull request within a repository. The ability to merge a pull request is determined by the repository's access permissions. The standard permission level required to merge pull requests is 'write' access. Users with this level of access can push changes to the repository and manage pull requests, including those automatically generated by Dependabot. Since the question specifies no custom configurations, these default GitHub permissions apply.

A. An enterprise administrator can merge pull requests, but this is not the minimum required permission. The 'write access' role is the more precise and fundamental requirement.

C. A user with 'read' access can only view repository content and open issues. They do not have the necessary permissions to merge pull requests or modify the repository's code.

D. Membership in an enterprise organization does not inherently grant merge permissions. A member must be assigned a specific role with at least 'write' access to the repository in question.

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1. GitHub Docs, "Repository roles for an organization." This document explicitly lists the abilities associated with each permission level. For the "Write" role, it includes the ability to "Merge pull requests."

Reference: In the table under the "Permissions" section, the row for "Merge pull requests" has a checkmark for the "Write," "Maintain," and "Admin" roles.

2. GitHub Docs, "Managing pull requests for dependency updates." This page clarifies that Dependabot pull requests are handled similarly to user-created ones.

Reference: Under the section "Viewing Dependabot pull requests," it states, "You can manage Dependabot pull requests in the same way as any other pull request..." This confirms that standard repository permissions apply.

3. GitHub Docs, "About Dependabot security updates." This document describes the process of Dependabot creating a pull request to fix a vulnerability, which is then reviewed and merged by repository maintainers.

Reference: Under the section "About pull requests for Dependabot security updates," it describes the pull request creation, implying it follows the standard workflow for review and merging by authorized users.